Pharmaceutical compositions of fumaric acid esters

ABSTRACT

Pharmaceutical compositions and dosage forms of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and/or methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate, containing low levels of certain impurities are disclosed.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority to U.S. Provisional Patent Application No. 61/969,488, which was filed Mar. 24, 2014 and is entitled Pharmaceutical Compositions of Fumaric Acid Esters. The contents of the above mentioned application is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

Disclosed herein are pharmaceutical compositions of fumaric acid di-esters having low levels of undesirable impurities.

BACKGROUND

(N,N-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is a di-ester of fumaric acid and a prodrug of monomethyl fumarate, and is also referred to as (N,N-Diethylcarbamoyl)methyl methyl fumarate. The compound has a molecular weight of 243 daltons and the following chemical structure:

The compound can synthesized by reacting monomethyl fumarate with 2-chloro-N,N-diethylacetamide in the presence of CsHCO₃. Other methods of synthesizing the compound are described in Gangakhedkar et al. U.S. Pat. No. 8,148,414.

Methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is also a di-ester of fumaric acid and a prodrug of monomethyl fumarate. The compound is also sometimes referred to as Methyl (4-morpholinobutyl) fumarate. The compound has a molecular weight of 271 daltons and the following chemical structure:

The compound can synthesized by activating monomethyl fumarate with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride in dichloromethane, followed by addition of 4-Morpholin-4ylbutyl-1-ol and 4-N,N-dimethylaminopyridine. Other methods of synthesizing the compound are described in Cundy et al. U.S. Patent Publication No. 2013/0203753, filed Feb. 7, 2013.

Fumaric acid esters have been proposed for use in treating a wide-variety of diseases and conditions involving immunological, autoimmune, and/or inflammatory processes including psoriasis (Joshi and Strebel, WO 1999/49858; U.S. Pat. No. 6,277,882; Mrowietz and Asadullah, Trends Mol Med 2005, 111(1), 43-48; and Yazdi and Mrowietz, Clinics Dermatology 2008, 26, 522-526); asthma and chronic obstructive pulmonary diseases (Joshi et al., WO 2005/023241 and US 2007/0027076); cardiac insufficiency including left ventricular insufficiency, myocardial infarction and angina pectoris (Joshi et al., WO 2005/023241; Joshi et al., US 2007/0027076); mitochondrial and neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease, Huntington's disease, retinopathia pigmentosa and mitochondrial encephalomyopathy (Joshi and Strebel, WO 2002/055063, US 2006/0205659, U.S. Pat. No. 6,509,376, U.S. Pat. No. 6,858,750, and U.S. Pat. No. 7,157,423); transplantation (Joshi and Strebel, WO 2002/055063, US 2006/0205659, U.S. Pat. No. 6,359,003, U.S. Pat. No. 6,509,376, and U.S. Pat. No. 7,157,423; and Lehmann et al., Arch Dermatol Res 2002, 294, 399-404); autoimmune diseases (Joshi and Strebel, WO 2002/055063, U.S. Pat. No. 6,509,376, U.S. Pat. No. 7,157,423, and US 2006/0205659) including multiple sclerosis (MS) (Joshi and Strebel, WO 1998/52549 and U.S. Pat. No. 6,436,992; Went and Lieberburg, US 2008/0089896; Schimrigk et al., Eur J Neurology 2006, 13, 604-610; and Schilling et al., Clin Experimental Immunology 2006, 145, 101-107); ischemia and reperfusion injury (Joshi et al., US 2007/0027076); AGE-induced genome damage (Heidland, WO 2005/027899); inflammatory bowel diseases such as Crohn's disease and ulcerative colitis; arthritis; and others (Nilsson et al., WO 2006/037342 and Nilsson and Muller, WO 2007/042034).

Many pharmaceutically active agents are susceptible to photodegradation upon exposure to sunlight and/or UV light. Generally, incorporation of light absorbers into formulations can stabilize these photosensitive agents to some extent. For example, N. Jamil et al. (“Studies of the photostability of reserpine in parenteral solutions”, Die Pharmazie, 38: 467-469 (1983)), refers to studies done on the photostability of reserpine in parenteral formulations and the effects of some commonly used stabilizers. U.S. Pat. No. 6,379,697, titled “Stabilization of photosensitive materials” to Gregoriadis, et al. refers to liposomes containing a photosensitive material together with a light absorbing material capable of increasing the photostability of the photosensitive material.

Griffin et al. (“The chemistry of photodimers of maleic and fumaric acid derivatives. I. Dimethyl fumarate dimer”, J Am Chem Soc (1961), 83: 2725-2728), disclose that dimethyl fumarate degrades in the presence of light to form the photodimer compound tetramethyl cyclobutane-1,2,3,4-tetracarboxylate. See also Griffin et al. U.S. Pat. No. 3,139,395.

SUMMARY

Thus, in a first aspect, a pharmaceutical dosage form for treating a disease in a patient is provided, comprising:

(a) a therapeutically effective amount of (N,N-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; and

(b) one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), or (XV):

N,N-diethyl-2-hydroxyacetamide, and salts of any of the foregoing, wherein: each of R¹ through R⁴ is independently chosen from hydrogen, methyl and (N,N-diethyl carbamoyl)methyl; each R⁵ and R⁷ is independently chosen from hydrogen, methyl, and (N,N-diethyl carbamoyl)methyl; Y is chosen from O, S, NH and NR⁸; R⁶ is chosen from hydrogen, lower alkyl, substituted lower alkyl, aryl, and substituted aryl; R⁸ is chosen from lower alkyl; each of R⁹ and R¹⁰ is independently chosen from hydrogen, methyl, and (N,N-diethyl carbamoyl)methyl; each of R¹¹ and R¹² is independently chosen from hydrogen, methyl, and (N,N-diethyl carbamoyl)methyl; each of R¹³ and R¹⁴ is independently chosen from hydrogen, methyl, and (N,N-diethyl carbamoyl)methyl; Q is —O—, —S—, —NH—, —N(R¹⁷)—, or —C(R¹⁸)₂—; each of R¹⁵ and R¹⁶ is independently chosen from hydrogen, methyl, and (N,N-diethyl carbamoyl)methyl; R¹⁷ is (N,N-diethylcarbamoyl)methyl or alkyl; each R¹⁸ is independently hydrogen or alkyl; each of R³⁷ and R³⁸ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl; R⁴¹ is (N,N-diethylcarbamoyl)methyl; R⁴² is chosen from hydrogen, ethyl, and (N,N-diethylcarbamoyl)methyl; and each of the one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), and (XV), and N,N-diethyl-2-hydroxy acetamide is present in the dosage form in an amount of less than 0.2% by weight based on total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, any one of the one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), and (XV), and N,N-diethyl-2-hydroxy acetamide is present in the dosage form in an amount of less than 0.1% by weight based on total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), and (XV), and N,N-diethyl-2-hydroxy acetamide is present in a combined total amount of less than 3% by weight based on total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), and (XV), and N,N-diethyl-2-hydroxy acetamide is present in a combined total amount of less than 2% by weight based on total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), and (XV) is selected from:

Formula (I) compounds 1,2-bis((N,N-diethylcarbamoyl)methoxycarbonyl)-3,4-bis(methoxycarbonyl)cyclobutane; 1,3-((N,N-diethylcarbamoyl)methoxycarbonyl)-2,4-bis(methoxycarbonyl)cyclobutane; 1-(N,N-diethylcarbamoyl)methoxycarbonyl-2-methoxycarbonylcyclobutane-3,4-dicarboxylic acid; 1,2-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-2,3-dicarboxylic acid; 1,3-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-2,4-dicarboxylic acid; 1,2-bis(methoxycarbonyl)cyclobutane-3,4-dicarboxylic acid; 1,3-bis(methoxycarbonyl)cyclobutane-2,4-dicarboylic acid; cyclobutane-1,2,3,4-tetracarboxylic acid; 1,2-((N,N-diethylcarbamoyl)methoxycarbonyl)-3-methoxycarbonylcyclobutane-4-carboxylic acid; 1,2-bis(methoxycarbonyl)cyclobutane-3,4-dicarboxylic acid; 1,2-bis(methoxycarbonyl)-3-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-4-carboxylic acid; 1,2-((N,N-diethylcarbamoyl)methoxycarbonyl)-3-(methoxycarbonyl)cyclobutane-4-carboxylic acid; 1-((N,N-diethylcarbamoyl)methoxycarbonyl)-2,3-bis(methoxycarbonyl)cyclobutane-4-carboxylic acid; 1-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-2,3,4-tricarboxylic acid; and 1-(methoxycarbonyl)cyclobutane-2,3,4-tricarboxylic acid; Formula (II) compounds (N,N-diethylcarbamoyl)methyl-methyl-hydroxysuccinate; methyl-hydroxysuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-hydroxysuccinic mono-acid; hydroxysuccinic acid; (N,N-diethylcarbamoyl)methyl-methyl-mercaptosuccinate; methylmercaptosuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-mercaptosuccinic mono-acid; mercaptosuccinic acid; (N,N-diethylcarbamoyl)methyl-methyl-aminosuccinate; methylaminosuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-aminosuccinic mono-acid; and aminosuccinic acid; Formula (III) compounds cis-(N,N-diethylcarbamoyl)methyl-methyl oxirane dicarboxylate; cis-(methoxycarbonyl)oxirane carboxylic mono-acid; cis-(N,N-diethylcarbamoyl)methoxycarbonyl oxirane carboxylic mono-acid; cis-oxirane 2,3-dicarboxylic acid; trans-(N,N-diethylcarbamoyl)methyl-methyl oxirane dicarboxylate; trans-(methoxycarbonyl)oxirane carboxylic mono-acid; trans-(N,N-diethylcarbamoyl)methoxycarbonyl oxirane carboxylic mono-acid; and trans-oxirane 2,3-dicarboxylic acid; Formula (IV) compounds (N,N-diethylcarbamoyl)methyl-methyl-succinate; methylsuccinic mono-acid; ((N,N-diethylcarbamoyl)methyl)succinic mono-acid; and succinic acid; Formula (V) compounds (N,N-diethylcarbamoyl)methyl-methyl-2,3-dihydroxysuccinate; methyl-2,3-dihydroxysuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-2,3-dihydroxysuccinic mono-acid; and 2,3-dihydroxysuccinic acid (tartaric acid); Formula (VI) compounds wherein:

Q is —O—, and each R¹⁵ and R¹⁶ is methyl;

Q is —O—, and each R¹⁵ and R¹⁶ is H;

Q is —O—, and each R¹⁵ and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —O—, R¹⁵ is H, and R¹⁶ is methyl;

Q is —O—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —O—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —S—, and each of R¹⁵ and R¹⁶ is methyl;

Q is —S—, and each of R¹⁵ and R¹⁶ is H;

Q is —S—, and each of R¹⁵ and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —S—, R¹⁵ is H, and R¹⁶ is methyl;

Q is —S—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —S—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NH—, and each of R¹⁵ and R¹⁶ is methyl;

Q is —NH—, and each of R¹⁵ and R¹⁶ is H;

Q is —NH—, and each of R¹⁵ and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NH—, R¹⁵ is H, and R¹⁶ is methyl;

Q is —NH—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NH—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NMe-, and each of R¹⁵ and R¹⁶ is methyl;

Q is —NMe-, and each of R¹⁵ and R¹⁶ is H;

Q is —NMe-, and each of R¹⁵ and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NMe-, R¹⁵ is H, and R¹⁶ is methyl;

Q is —NMe-, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NMe-, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —CH₂—, and each R¹⁵ and R¹⁶ is methyl;

Q is —CH₂—, and each R¹⁵ and R¹⁶ is H;

Q is —CH₂—, and each R¹⁵ and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —CH₂—, R¹⁵ is H, and R¹⁶ is methyl;

Q is —CH₂—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; and

Q is —CH₂—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Formula (XIII) compounds (N,N-diethylcarbamoyl)methyl methyl maleate, (N,N-diethylcarbamoyl)methyl maleic acid, bis(N,N-diethylcarbamoyl)methyl maleate, dimethyl maleate, methyl maleate, and maleic acid;

Formula (XV) compounds (2E)-3-(((N,N-diethylcarbamoyl)methyl)oxycarbonyl)prop-2-enoic acid; (N,N-diethylcarbamoyl)methyl ethyl (2E)but-2-ene-1,4-dioate; and bis(N,N-diethylcarbamoyl)methyl(2E)but-2-ene-1,4-dioate;

isomers of any of the foregoing compounds and salts of any of the foregoing compounds.

In some embodiments, the dosage form contains one or more compounds of Formula (I), wherein the one or more compounds of Formula (I) are 1R,2R,3S,4S-isomers. In some embodiments, the dosage form includes a pharmaceutically acceptable vehicle. In some embodiments, the pharmaceutically acceptable vehicle is selected from a carrier, a diluent, an excipient, a wetting agent, an emulsifier, a buffer, a stabilizer, a thickener, a lubricant, a coloring agent, and combinations thereof. In some embodiments, the dosage form is in the form of a tablet or capsule.

In some embodiments, the dosage form contains a compound of Formula (I), comprising an opaque layer that is free of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the opaque layer is a coating. In some embodiments, the opaque layer comprises a gelatin capsule comprising an opaque material. In some embodiments, the dosage form is enclosed in a package that limits exposure of the dosage form to ambient light. In some embodiments, the package is a bottle comprising an opaque polymer. In some embodiments, the package is a blister pack comprising metal foil, an opaque polymer or a combination thereof.

In some embodiments, the dosage form contains a compound of Formula (II), wherein the dosage form is substantially free of materials that promote addition reactions of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the dosage form is substantially free of alcohols, mercaptans, alkylamines and dialkylamines. In some embodiments, the dosage form is substantially free of R⁶OH, R⁶SH, R⁶NH₂, and R⁶N(H)R⁸; wherein each of R⁶ and R⁸ is alkyl.

In some embodiments, the dosage form contains a compound of Formula (III), wherein the dosage form is substantially free of PVP, PEG, and polysorbate surfactant. In some embodiments, the dosage form contain compound of Formula (III), comprising an antioxidant, a free radical scavenger or a combination thereof. In some embodiments, the one or more compounds of Formula (III) comprises (N,N-diethylcarbamoyl)methyl methyl oxirane-2,3-dicarboxylate.

In some embodiments, the dosage form contains a compound of Formula (IV), wherein the dosage form is substantially free of any compound capable of facilitating the reduction of the double bond of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the dosage form is substantially free of any compounds containing a hydrazino group.

In some embodiments, the dosage form contains a compound of Formula (V), comprising an antioxidant, a free radical scavenger or a combination thereof.

In some embodiments, the dosage form contains a compound of Formula (VI), wherein the dosage form is substantially free of materials that are capable of reacting with (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate to form Diels-Alder products. In some embodiments, the dosage form is substantially free of compounds containing cyclopentadiene, furan, thiophene, and pyrrole moieties.

In some embodiments, a method of treating a disease in a patient comprises administering to the patient a dosage form as described above. In some embodiments, the disease is selected from multiple sclerosis and psoriasis. In some embodiments, the disease is selected from adrenal leukodystrophy, AGE-induced genome damage, Alexander Disease, Alper's Disease, Alzheimer's disease, amyotrophic lateral sclerosis, angina pectoris, arthritis, asthma, balo concentric sclerosis, Canavan disease, cardiac insufficiency including left ventricular insufficiency, central nervous system vasculitis, Charcott-Marie-Tooth Disease, childhood ataxia with central nervous system hypomyelination, chronic idiopathic peripheral neuropathy, chronic obstructive pulmonary disease, diabetic retinopathy, graft versus host disease, hepatitis C viral infection, herpes simplex viral infection, human immunodeficiency viral infection, Huntington's disease, irritable bowel disorder, ischemia, Krabbe Disease, lichen planus, macular degeneration, mitochondrial encephalomyopathy, monomelic amyotrophy, multiple sclerosis, myocardial infarction, neurodegeneration with brain iron accumulation, neuromyelitis optica, neurosarcoidosis, NF-κB mediated diseases, optic neuritis, paraneoplastic syndromes, Parkinson's disease, Pelizaeus-Merzbacher disease, primary lateral sclerosis, progressive supranuclear palsy, psoriasis, reperfusion injury, retinopathia pigmentosa, Schilder's Disease, subacute necrotizing myelopathy, Susac's syndrome, transplantation rejection, transverse myelitis, a tumor, ulcerative colitis, Zellweger's syndrome, granulomas including annulaire, pemphigus, bollus pemphigoid, Behcet's disease, contact dermatitis, acute dermatitis, chronic dermatitis, alopecia areata (totalis and universalis), sarcoidosis, cutaneous sarcoidosis, pyoderma gangrenosum, cutaneous lupus, Crohn's disease, and cutaneous Crohn's disease.

In a second aspect, a pharmaceutical dosage form for treating a disease in a patient is provided, comprising:

(a) a therapeutically effective amount of Methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; and

(b) one or more compounds of Formulae (VII), (VIII), (IX), (X), (XI), (XII), (XIV), or (XVI):

4-morpholin-4-ylbutan-1-ol, and salts of any of the foregoing, wherein: each of R¹⁹ through R²² is independently chosen from hydrogen, methyl, and 4-morpholin-4-ylbutyl; each R²³ and R²⁵ is independently chosen from hydrogen, methyl, and 4-morpholin-4-ylbutyl; Y is chosen from O, S, NH and NR²⁶; R²⁴ is chosen from hydrogen, lower alkyl, substituted lower alkyl, aryl, and substituted aryl; R²⁶ is chosen from lower alkyl; each of R²⁷ and R²⁸ is independently chosen from hydrogen, methyl, and 4-morpholin-4-ylbutyl; each of R²⁹ and R³⁹ is independently chosen from hydrogen, methyl, and 4-morpholin-4-ylbutyl; each of R³¹ and R³² is independently chosen from hydrogen, methyl, and 4-morpholin-4-ylbutyl; Q is —O—, —S—, —NH—, —N(R³⁵)—, or —C(R³⁶)₂—; each of R³³ and R³⁴ is independently chosen from hydrogen, methyl, and 4-morpholin-4-ylbutyl; R³⁵ is 4-morpholin-4-ylbutyl or alkyl; each R³⁶ is independently hydrogen or alkyl; each of R³⁹ and R⁴⁰ is independently chosen from hydrogen, methyl, and 4-morpholin-4-ylbutyl; R⁴³ is 4-morpholin-4-ylbutyl; R⁴⁴ is chosen from hydrogen, ethyl, and 4-morpholin-4-ylbutyl; and each of the one or more compounds of Formulae (VII), (VIII), (IX), (X), (XI), (XII), (XIV), and (XVI), and 4-morpholin-4-ylbutan-1-ol are present in the dosage form in an amount of less than 0.2% by weight based on total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, any one of the one or more compounds of Formulae (VII), (VIII), (IX), (X), (XI), (XII), (XIV), and (XVI), and 4-morpholin-4-ylbutan-1-ol are present in the dosage form in an amount of less than 0.1% by weight based on total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formulae (VII), (VIII), (IX), (X), (XI), (XII), (XIV), and (XVI), and 4-morpholin-4-ylbutan-1-ol are present in a combined total amount of less than 3% by weight based on total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formulae (VII), (VIII), (IX), (X), (XI), (XII), (XIV), and (XVI), and 4-morpholin-4-ylbutan-1-ol are present in a combined total amount of less than 2% by weight based on total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formulae (VII), (VIII), (IX), (X), (XI), (XII), (XIV), and (XVI) are selected from:

Formula (VII) compounds 1,2-bis(methoxycarbonyl)-3,4-bis(4-morpholin-4-ylbutoxycarbonyl)cyclobutane; 1,3-bis(methoycarbonyl)-2,4-bis(4-morpholin-4-ylbutoxycarbonyl)cyclobutane; 1-methoxycarbonyl-2-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-3,4-dicarboxylic acid; 1,2-bis(methoxycarbonyl)cyclobutane-2,3-dicarboxylic acid; 1,3-bis(methoxycarbonyl)cyclobutane-2,4-dicarboxylic acid; 1,2-bis-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-3,4-dicarboylic acid; 1,3-bis-(4-morpholin-4-ylbutyl)cyclobutane-2,4-dicarboylic acid; cyclobutane-1,2,3,4-tetracarboxylic acid; 1,2-bis(methoxycarbonyl)-3-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-4-carboxylic acid; 1,2-bis-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-3,4-dicarboxylic acid; 1,2-bis(4-morpholin-4-ylbutoxycarbonyl)-3-(methoxycarbonyl)cyclobutane-4-carboxylic acid; 1,2-bis(methoxycarbonyl)-3-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-4-carboxylic acid; 1-methoxycarbonyl-2,3-bis-(4-morpholin-4-ylbutoxycarbonyl) cyclobutane-4-carboxylic acid; 1-(methoxycarbonyl)cyclobutane-2,3,4-tricarboxylic acid; and 1-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-2,3,4-tricarboxylic acid; Formula (VIII) compounds methyl-(4-morpholin-4-ylbutyl)-hydroxysuccinate; (4-morpholin-4-ylbutyl)-hydroxysuccinic mono-acid; methylhydroxysuccinic mono-acid; hydroxysuccinic acid; methyl-(4-morpholin-4-ylbutyl)-mercaptosuccinate; (4-morpholin-4-ylbutyl)-mercaptosuccinic mono-acid; methyl-mercaptosuccinic mono-acid; mercaptosuccinic acid; methyl-(4-morpholin-4-ylbutyl)-aminosuccinate; (4-morpholin-4-ylbutyl)-aminosuccinic mono-acid; methylaminosuccinic mono-acid; and aminosuccinic acid; Formula (IX) compounds cis-methyl-(4-morpholin-4-ylbutyl)-oxirane dicarboxylate; cis-(4-morpholin-4-ylbutoxycarbonyl)-oxirane carboxylic mono-acid; cis-methoxycarbonyloxirane carboxylic mono-acid; cis-oxirane 2,3-dicarboxylic acid; trans-methyl-(4-morpholin-4-ylbutoxycarbonyl)-oxirane dicarboxylate; trans-(4-morpholin-4-ylbutoxycarbonyl)-oxirane carboxylic mono-acid; trans-(methoxycarbonyl)oxirane carboxylic mono-acid; and trans-oxirane 2,3-dicarboxylic acid; Formula (X) compounds methyl-(4-morpholin-4-ylbutyl)-succinate; (4-morpholin-4-ylbutyl)-succinic mono-acid; methylsuccinic mono-acid; and succinic acid; Formula (XI) compounds methyl-(4-morpholin-4-ylbutyl)-2,3-dihydroxysuccinate; (4-morpholin-4-ylbutyl)-2,3-dihydroxysuccinic mono-acid; methyl-2,3-dihydroxysuccinic mono-acid; and 2,3-dihydroxysuccinic acid (tartaric acid); Formula (XII) compounds wherein:

Q is —O—, and each R³³ and R³⁴ is methyl;

Q is —O—, and each R³³ and R³⁴ is H;

Q is —O—, and each R³³ and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —O—, R³³ is H, and R³⁴ is methyl;

Q is —O—, R³³ is H, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —O—, R³³ is methyl, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —S—, and each of R³³ and R³⁴ is methyl;

Q is —S—, and each of R³³ and R³⁴ is H;

Q is —S—, and each of R³³ and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —S—, R³³ is H, and R³⁴ is methyl;

Q is —S—, R³³ is H, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —S—, R³³ is methyl, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NH—, and each of R³³ and R³⁴ is methyl;

Q is —NH—, and each of R³³ and R³⁴ is H;

Q is —NH—, and each of R³³ and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NH—, R³³ is H, and R³⁴ is methyl;

Q is —NH—, R³³ is H, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NH—, R³³ is methyl, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NMe-, and each of R³³ and R³⁴ is methyl;

Q is —NMe-, and each of R³³ and R³⁴ is H;

Q is —NMe-, and each of R³³ and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NMe-, R³³ is H, and R³⁴ is methyl;

Q is —NMe-, R³³ is H, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NMe-, R³³ is methyl, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —CH₂—, and each R³³ and R³⁴ is methyl;

Q is —CH₂—, and each R³³ and R³⁴ is H;

Q is —CH₂—, and each R³³ and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —CH₂—, R³³ is H, and R³⁴ is methyl;

Q is —CH₂—, R³³ is H, and R³⁴ is 4-morpholin-4-ylbutyl; and

Q is —CH₂—, R³³ is methyl, and R³⁴ is 4-morpholin-4-ylbutyl;

Formula (XIV) compounds 4-morpholin-4-ylbutyl methyl maleate, 4-morpholin-4-ylbutyl maleic acid, bis(4-morpholin-4-ylbutyl) maleate, dimethyl maleate, methyl maleate, and maleic acid;

Formula (XVI) compounds (2E)-3-((4-morpholin-4-ylbutyl)oxycarbonyl)prop-2-enoic acid; ethyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-diate; and bis-(4-morpholin-4-ylbutyl) (2E)but-2-ene-1,4-dioate;

isomers of any of the foregoing compounds and salts of any of the foregoing compounds.

In some embodiments, the dosage form contains one or more compounds of Formula (VII), wherein the one or more compounds of Formula (VII) are 1R,2R,3S,4S-isomers. In some embodiments, the dosage form includes a pharmaceutically acceptable vehicle. In some embodiments, the pharmaceutically acceptable vehicle is selected from a carrier, a diluent, an excipient, a wetting agent, an emulsifier, a buffer, a stabilizer, a thickener, a lubricant, a coloring agent and combinations thereof. In some embodiments, the dosage form is in the form of a tablet or capsule.

In some embodiments, the dosage form contains a compound of Formula (VII), comprising an opaque layer that is free of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the opaque layer is a coating. In some embodiments, the opaque layer comprises a gelatin capsule comprising an opaque material. In some embodiments, the dosage form is enclosed in a package that limits exposure of the dosage form to ambient light. In some embodiments, the package is a bottle comprising an opaque polymer. In some embodiments, the package is a blister pack comprising metal foil, an opaque polymer or a combination thereof.

In some embodiments, the dosage form contains a compound of Formula (VIII), wherein the dosage form is substantially free of materials that promote addition reactions of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the dosage form is substantially free of alcohols, mercaptans, alkylamines and dialkylamines. In some embodiments, the dosage form is substantially free of R²⁴OH, R²⁴SH, R²⁴NH₂, and R²⁴N(H)R²⁶; wherein each of R²⁴ and R²⁶ is alkyl. In some embodiments, the dosage form contained a compound of Formula (X), wherein the dosage form is substantially free of any compound capable of facilitating the reduction of the double bond of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the dosage form is substantially free of any compounds containing a hydrazino group.

In some embodiments, the dosage form contains a compound of Formula (IX), wherein the dosage form is substantially free of PVP, PEG and polysorbate surfactant. In some embodiments, the dosage form contains a compound of Formula (IX), comprising an antioxidant, a free radical scavenger or a combination thereof. In some embodiments, the one or more compounds of Formula (IX) comprises methyl 4-morpholin-4-ylbutyl oxirane-2,3-dicarboxylate.

In some embodiments, the dosage form contains a compound of Formula (XI), comprising an antioxidant, a free radical scavenger or a combination thereof.

In some embodiments, the dosage form contained a compound of Formula (XII), wherein the dosage form is substantially free of materials that are capable of reacting with methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate to form Diels-Alder products. In some embodiments, the dosage form is substantially free of compounds containing cyclopentadiene, furan, thiophene, and pyrrole moieties.

In some embodiments, a method of treating a disease in a patient is provided, comprising administering to the patient a dosage form as described above. In some embodiments, the disease is selected from multiple sclerosis and psoriasis. In some embodiments, the disease is selected from adrenal leukodystrophy, AGE-induced genome damage, Alexander Disease, Alper's Disease, Alzheimer's disease, amyotrophic lateral sclerosis, angina pectoris, arthritis, asthma, balo concentric sclerosis, Canavan disease, cardiac insufficiency including left ventricular insufficiency, central nervous system vasculitis, Charcott-Marie-Tooth Disease, childhood ataxia with central nervous system hypomyelination, chronic idiopathic peripheral neuropathy, chronic obstructive pulmonary disease, diabetic retinopathy, graft versus host disease, hepatitis C viral infection, herpes simplex viral infection, human immunodeficiency viral infection, Huntington's disease, irritable bowel disorder, ischemia, Krabbe Disease, lichen planus, macular degeneration, mitochondrial encephalomyopathy, monomelic amyotrophy, multiple sclerosis, myocardial infarction, neurodegeneration with brain iron accumulation, neuromyelitis optica, neurosarcoidosis, NF-κB mediated diseases, optic neuritis, paraneoplastic syndromes, Parkinson's disease, Pelizaeus-Merzbacher disease, primary lateral sclerosis, progressive supranuclear palsy, psoriasis, reperfusion injury, retinopathia pigmentosa, Schilder's Disease, subacute necrotizing myelopathy, Susac's syndrome, transplantation rejection, transverse myelitis, a tumor, ulcerative colitis, Zellweger's syndrome, granulomas including annulaire, pemphigus, bollus pemphigoid, Behcet's disease, contact dermatitis, acute dermatitis, chronic dermatitis, alopecia areata (totalis and universalis), sarcoidosis, cutaneous sarcoidosis, pyoderma gangrenosum, cutaneous lupus, Crohn's disease and cutaneous Crohn's disease.

The compositions and dosage forms disclosed herein can be used to treat any number of diseases for which FAEs are known or thought to be therapeutically effective. In several aspects, the compositions and dosage forms disclosed herein can be used to treat multiple sclerosis and psoriasis.

Additional embodiments and features are set forth in part in the description that follows, and in part will become apparent to those skilled in the art upon examination of the specification, or may be learned by the practice of the embodiments discussed herein. A further understanding of the nature and advantages of certain embodiments may be realized by reference to the remaining portions of the specification and the drawings, which forms a part of this disclosure.

Definitions

A dash (“-”) that is not between two letters or symbols is used to indicate a point of attachment for a moiety or substituent. For example, —CONH₂ is bonded through the carbon atom.

“Alkyl” refers to a saturated or unsaturated, branched, or straight-chain, monovalent hydrocarbon radical derived by the removal of one hydrogen atom from a single carbon atom of a parent alkane, alkene, or alkyne. Examples of alkyl groups include, but are not limited to, methyl; ethyls such as ethanyl, ethenyl, and ethynyl; propyls such as propan-1-yl, propan-2-yl, prop-1-en-1-yl, prop-1-en-2-yl, prop-2-en-1-yl (allyl), prop-1-yn-1-yl, prop-2-yn-1-yl, etc.; butyls such as butan-1-yl, butan-2-yl, 2-methyl-propan-1-yl, 2-methyl-propan-2-yl, but-1-en-1-yl, but-1-en-2-yl, 2-methyl-prop-1-en-1-yl, but-2-en-1-yl, but-2-en-2-yl, buta-1,3-dien-1-yl, buta-1,3-dien-2-yl, but-1-yn-1-yl, but-1-yn-3-yl, but-3-yn-1-yl, etc.; and the like.

The term “alkyl” is specifically intended to include groups having any degree or level of saturation, i.e., groups having exclusively single carbon-carbon bonds, groups having one or more double carbon-carbon bonds, groups having one or more triple carbon-carbon bonds, and groups having combinations of single, double, and triple carbon-carbon bonds. Where a specific level of saturation is intended, the terms alkanyl, alkenyl, and alkynyl are used. In certain embodiments, an alkyl group can have from 1 to 20 carbon atoms (C₁₋₂₀) in certain embodiments, from 1 to 10 carbon atoms (C₁₋₁₀), in certain embodiments from 1 to 8 carbon atoms (C₁₋₈), in certain embodiments, from 1 to 6 carbon atoms (C₁₋₆), in certain embodiments from 1 to 4 carbon atoms (C₁₋₄), and in certain embodiments, from 1 to 3 carbon atoms (C₁₋₃).

The term “alkyl” is specifically intended to include lower alkyl groups. As used herein, the phrase “lower alkyl” refers to a saturated or unsaturated, branched, or straight-chain, monovalent hydrocarbon radical of six or fewer carbon atoms, derived by the removal of one hydrogen atom from a single carbon atom of a parent alkane, alkene, or alkyne. In certain embodiments, a lower alkyl group can have from 1 to 6 carbon atoms (C₁₋₆), in certain embodiments from 1 to 5 carbon atoms (C₁₋₅), in certain embodiments from 1 to 4 carbon atoms (C₁₋₄), in certain embodiments, from 1 to 3 carbon atoms (C₁₋₃), in certain embodiments from 1 to 2 carbon atoms (C₁₋₂) and in certain embodiments a single carbon atom. Examples of lower alkyl groups include, but are not limited to, methyl, ethyl, propyl, n-propyl, isopropyl, butyl, isobutyl, n-butyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, isohexyl, etc., and the like.

“Aryl” refers to a monovalent aromatic hydrocarbon radical derived by the removal of one hydrogen atom from a single carbon atom of a parent aromatic ring system. Aryl benzene; bicyclic ring systems wherein at least one ring is carbocyclic and aromatic, for example, naphthalene, indane, and tetralin; and tricyclic ring systems wherein at least one ring is carbocyclic and aromatic, for example, fluorene. Aryl encompasses multiple ring systems having at least one carbocyclic aromatic ring fused to at least one carbocyclic aromatic ring, cycloalkyl ring, or heterocycloalkyl ring. For example, aryl includes a phenyl ring fused to a 5- to 7-membered heterocycloalkyl ring containing one or more heteroatoms chosen from N, O, and S. For such fused, bicyclic ring systems wherein only one of the rings is a carbocyclic aromatic ring, the radical carbon atom may be at the carbocyclic aromatic ring or at the heterocycloalkyl ring. Examples of aryl groups include, but are not limited to, groups derived from aceanthrylene, acenaphthylene, acephenanthrylene, anthracene, azulene, benzene, chrysene, coronene, fluoranthene, fluorene, hexacene, hexaphene, hexalene, as-indacene, s-indacene, indane, indene, naphthalene, octacene, octaphene, octalene, ovalene, penta-2,4-diene, pentacene, pentalene, pentaphene, perylene, phenalene, phenanthrene, picene, pleiadene, pyrene, pyranthrene, rubicene, triphenylene, trinaphthalene, and the like. In certain embodiments, an aryl group can have from 6 to 20 carbon atoms (C₆₋₂₀), from 6 to 12 carbon atoms (C₆₋₁₂), from 6 to 10 carbon atoms (C₆₋₁₀), and in certain embodiments from 6 to 8 carbon atoms (C₆₋₈). Aryl, however, does not encompass or overlap in any way with heteroaryl, separately defined herein.

“Compounds” refers to chemical substances consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together in a defined spatial arrangement by chemical bonds. Compounds include any specific compounds within a given chemical formula. Compounds may be identified either by their chemical structure and/or chemical name. Compounds are named using Chemistry 4-D Draw Pro, version 7.01c (ChemInnovation Software, Inc., San Diego, Calif.). When the chemical structure and chemical name conflict, the chemical structure is determinative of the identity of the compound. The compounds described herein may comprise one or more chiral centers and/or double bonds and therefore may exist as stereoisomers such as double-bond isomers (i.e., geometric isomers), enantiomers, or diastereomers. Accordingly, any chemical structures within the scope of the specification depicted, in whole or in part, with a relative configuration encompasses all possible enantiomers and stereoisomers of the illustrated compounds including the stereoisomerically pure form (e.g., geometrically pure, enantiomerically pure, or diastereomerically pure) and enantiomeric and stereoisomeric mixtures. Enantiomeric and stereoisomeric mixtures may be resolved into their component enantiomers or stereoisomers using separation techniques or chiral synthesis techniques well known to the skilled artisan. Compounds include, but are not limited to, optical isomers, racemates, and other mixtures. In such embodiments, a single enantiomer or diastereomer, i.e., optically active form can be obtained by asymmetric synthesis or by resolution of the racemates. Resolution of the racemates may be accomplished, for example, by conventional methods such as crystallization in the presence of a resolving agent, or chromatography using, for example, chiral stationary phases. Notwithstanding the foregoing, in the compounds monomethyl fumarate, dimethyl fumarate, and (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate, the configuration of the illustrated double bond is only in the E configuration (i.e. trans configuration).

Compounds may also exist in several tautomeric forms including the enol form, the keto form, and mixtures thereof. Accordingly, the chemical structures depicted herein encompass all possible tautomeric forms of any illustrated compounds. Compounds also include isotopically labeled compounds where one or more atoms have an atomic mass different from the atomic mass conventionally found in nature. Examples of isotopes that may be incorporated into the compounds disclosed herein include, but are not limited to ²H, ³H, ¹¹C, ¹³C, ¹⁴C, ¹⁵N, ¹⁸O, ¹⁷O, etc. Compounds may exist in unsolvated forms as well as solvated forms, including hydrated forms and as N-oxides. In general, compounds as referred to herein may be free acid, hydrated, solvated, or N-oxides. Compounds may exist in one or more ionic forms. Certain compounds may exist in multiple crystalline, co-crystalline, or amorphous forms. Compounds include pharmaceutically acceptable salts, or pharmaceutically acceptable solvates of the free acid form of any of the foregoing, as well as crystalline forms of any of the foregoing.

Compounds also include solvates. A solvate refers to a molecular complex of a compound with one or more solvent molecules in a stoichiometric or non-stoichiometric amount. Such solvent molecules are those commonly used in the pharmaceutical art, which are known to be innocuous to a patient, e.g., water, ethanol, and the like. A molecular complex of a compound or moiety of a compound and a solvent can be stabilized by non-covalent intra-molecular forces such as, for example, electrostatic forces, van der Waals forces, or hydrogen bonds. The term “hydrate” refers to a solvate in which the one or more solvent molecules is water.

Further, when partial structures of compounds are illustrated, an asterisk (*) indicates the point of attachment of the partial structure to the rest of the molecule. “Dimethyl fumarate” refers to the dimethyl ester of fumaric acid. The compound has a molecular weight of 144.13 daltons and the following chemical structure:

This compound is also known by the names Dimethyl (E)-butenedioate (IUPAC), trans-1,2-Ethylenedicarboxylic acid dimethyl ester and (E)-2-Butenedioic acid dimethyl ester. The compound is also referred to by the acronym DMF. DMF can be synthesized according to the methods described in Chinese Patent Publication CN 101318901A, the disclosures of which are incorporated herein by reference.

“Disease” refers to a disease, disorder, condition, or symptom of any of the foregoing.

“Drug” as defined under 21 U.S.C. § 321(g)(1) means (A) articles recognized in the official United States Pharmacopoeia, official Homeopathic Pharmacopoeia of the United States, or official National Formulary, or any supplement to any of them; and (B) articles intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease in man or other animals; and (C) articles (other than food) intended to affect the structure or any function of the body of man or other animals.

“Monomethyl fumarate” refers to the monomethyl ester of fumaric acid. The compound has a molecular weight of 130.10 daltons and the following chemical formula:

The compound is also commonly referred to as 2(E)-Butenedioic acid 1-methyl ester; (2E)-4-Methoxy-4-oxobut-2-enoic acid; Fumaric acid hydrogen 1-methyl ester; (2E)-2-Butenedioic acid 1-methyl ester; (E)-2-Butenedioic acid monomethyl ester; Monomethyl trans-ethylene-1,2-dicarboxylate; and methyl hydrogen fumarate. The compound is also referred to herein and elsewhere by the acronyms MMF and/or MHF. MMF can be synthesized according to the methods described in Dymicky, Preparation of Monomethyl Fumarate, Organic Preparations and Procedures International: The New Journal for Organic Synthesis, Vol 14, Issue 4, 1983; and Spatz et al., J. Org. Chem., 1958, 23 (10), 1559-1560.

“Multiple sclerosis” also known as “disseminated sclerosis” or “encephalomyelitis disseminata”, and sometimes referred to by the acronym MS, is an inflammatory disease in which the fatty myelin sheaths around the axons of the brain and spinal cord are damaged, leading to demyelination and scarring as well as a broad spectrum of signs and symptoms. Disease onset usually occurs in young adults, and it is more common in women. It has a prevalence that ranges between 2 and 150 per 100,000.

MS affects the ability of nerve cells in the brain and spinal cord to communicate with each other effectively. Nerve cells communicate by sending electrical signals called action potentials down long fibers called axons, which are contained within an insulating substance called myelin. In MS, the body's own immune system attacks and damages the myelin. When myelin is lost, the axons can no longer effectively conduct signals. The name multiple sclerosis refers to scars (sclerae-better known as plaques or lesions) particularly in the white matter of the brain and spinal cord, which is mainly composed of myelin. Although much is known about the mechanisms involved in the disease process, the cause remains unknown. Theories include genetics or infections. Different environmental risk factors have also been found.

Almost any neurological symptom can appear with the disease, and the disease often progresses to physical and cognitive disability. MS takes several forms, with new symptoms occurring either in discrete attacks (relapsing forms) or accumulating over time (progressive forms). Between attacks, symptoms may go away completely, but permanent neurological deficits often occur, especially as the disease advances.

“Patient” refers to a mammal, for example, a human.

“Pharmaceutically acceptable” refers to approved or approvable by a regulatory agency of the Federal or a state government or listed in the U.S. Pharmacopoeia or other generally recognized pharmacopoeia for use in animals, and more particularly in humans.

“Pharmaceutically acceptable salt” refers to a salt of a compound, which possesses the desired pharmacological activity of the parent compound. Such salts include acid addition salts, formed with inorganic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, and the like; or formed with organic acids such as acetic acid, propionic acid, hexanoic acid, cyclopentanepropionic acid, glycolic acid, pyruvic acid, lactic acid, malonic acid, succinic acid, malic acid, maleic acid, fumaric acid, tartaric acid, citric acid, benzoic acid, 3-(4-hydroxybenzoyl) benzoic acid, cinnamic acid, mandelic acid, methanesulfonic acid, ethanesulfonic acid, 1,2-ethane-disulfonic acid, 2-hydroxyethanesulfonic acid, benzenesulfonic acid, 4-chlorobenzenesulfonic acid, 2-naphthalenesulfonic acid, 4-toluenesulfonic acid, camphorsulfonic acid, 4-methylbicyclo[2.2.2]-oct-2-ene-1-carboxylic acid, glucoheptonic acid, 3-phenylpropionic acid, trimethylacetic acid, tertiary butylacetic acid, lauryl sulfuric acid, gluconic acid, glutamic acid, hydroxynaphthoic acid, salicylic acid, stearic acid, muconic acid, and the like; and salts formed when an acidic proton present in the parent compound is replaced by a metal ion, e.g., an alkali metal ion, an alkaline earth ion, or an aluminum ion; or coordinates with an organic base such as ethanolamine, diethanolamine, triethanolamine, N-methylglucamine, and the like. In certain embodiments, a pharmaceutically acceptable salt is the hydrochloride salt. In certain embodiments, a pharmaceutically acceptable salt is the sodium salt.

“Pharmaceutically acceptable vehicle” refers to a pharmaceutically acceptable diluent, a pharmaceutically acceptable adjuvant, a pharmaceutically acceptable excipient, a pharmaceutically acceptable carrier, or a combination of any of the foregoing with which a compound provided by the present disclosure may be administered to a patient, which does not destroy the pharmacological activity thereof and which is non-toxic when administered in doses sufficient to provide a therapeutically effective amount of the compound.

“Pharmaceutical composition” refers to a therapeutically active compound and at least one pharmaceutically acceptable vehicle, with which the compound is administered to a patient.

“Polyethylene glycol” and “PEG” each refer to a linear polymer formed by the addition reaction of ethylene glycol with ethylene oxide. PEG is commercially available in average molecular weights ranging from about 200 to greater than 20,000. The commercially available grades of polyethylene glycol are marketed based on the average molecular weight, e.g., the grade nomenclature is identified with the molecular weight. For example, PEG 400 represents material with an average molecular weight of 400 and the material with an average molecular weight of 600 is known as PEG 600. PEG 200, 300, 400, and 600 are clear viscous liquids at room temperature; PEG 900, 1000, 1450, 3350, 4500 and 8000 are white, waxy solids.

“Polyvinylpyrrolidone” and “PVP” each refer to a linear polymer of 1-vinyl-2-pyrrolidone. PVP, also known as Povidone, is commercially available as a series of products having mean molecular weights ranging from about 10,000 to about 700,000. The various products are marketed according to average molecular weights designated K-values; e.g., GAF Corporation supplies PVP having K-value=15 as having an average molecular weight of about 10,000, and K-value=30 as having an average molecular weight of about 40,000.

“Psoriasis” is an immune-mediated disease that affects the skin. It is typically a lifelong condition. Psoriasis occurs when the immune system mistakes a normal skin cell for a pathogen, and sends out faulty signals that cause overproduction of new skin cells. There are five types of psoriasis: plaque, guttate, inverse, pustular, and erythrodermic. The most common form, plaque psoriasis, is commonly seen as red and white hues of scaly patches appearing on the top first layer of the epidermis (skin) Some patients, though, have no dermatological signs or symptoms. The name psoriasis is from the Greek word, meaning roughly “itching condition” (psora “itch”+-sis “action, condition”).

In plaque psoriasis, skin rapidly accumulates at these sites, which gives it a silvery-white appearance. Plaques frequently occur on the skin of the elbows and knees, but can affect any area, including the scalp, palms of hands and soles of feet, and genitals. In contrast to eczema, psoriasis is more likely to be found on the outer side of the joint.

The disorder is a chronic recurring condition that varies in severity from minor localized patches to complete body coverage. Fingernails and toenails are frequently affected (psoriatic nail dystrophy) and can be seen as an isolated sign. Psoriasis can also cause inflammation of the joints, which is known as psoriatic arthritis. Between 10% and 30% of all people with psoriasis also have psoriatic arthritis.

The cause of psoriasis is not fully understood, but it is believed to have a genetic component and local psoriatic changes can be triggered by an injury to the skin known as the Koebner phenomenon. Various environmental factors have been suggested as aggravating to psoriasis, including oxidative stress, stress, withdrawal of systemic corticosteroid, as well as other environmental factors, but few have shown statistical significance.

“Treating” or “treatment” of any disease refers to reversing, alleviating, arresting, or ameliorating a disease or at least one of the clinical symptoms of a disease, reducing the risk of acquiring a disease or at least one of the clinical symptoms of a disease, inhibiting the progress of a disease or at least one of the clinical symptoms of the disease or reducing the risk of developing a disease or at least one of the clinical symptoms of a disease. “Treating” or “treatment” also refers to inhibiting the disease, either physically, (e.g., stabilization of a discernible symptom), physiologically, (e.g., stabilization of a physical parameter), or both, and to inhibiting at least one physical parameter that may or may not be discernible to the patient. In certain embodiments, “treating” or “treatment” refers to delaying the onset of the disease or at least one or more symptoms thereof in a patient which may be exposed to or predisposed to a disease even though that patient does not yet experience or display symptoms of the disease.

“Therapeutically effective amount” refers to the amount of a compound that, when administered to a subject for treating a disease, or at least one of the clinical symptoms of a disease, is sufficient to affect such treatment of the disease or symptom thereof. The “therapeutically effective amount” may vary depending, for example, on the compound, the disease and/or symptoms of the disease, severity of the disease and/or symptoms of the disease or disorder, the age, weight, and/or health of the patient to be treated, and the judgment of the prescribing physician. An appropriate amount in any given instance may be ascertained by those skilled in the art or capable of determination by routine experimentation.

“Therapeutically effective dose” refers to a dose that provides effective treatment of a disease or disorder in a patient. A therapeutically effective dose may vary from compound to compound, and from patient to patient, and may depend upon factors such as the condition of the patient and the route of delivery. A therapeutically effective dose may be determined in accordance with routine pharmacological procedures known to those skilled in the art.

DETAILED DESCRIPTION

Reference is now made in detail to certain embodiments of pharmaceutical compositions of monomethyl fumarate. The disclosed embodiments are not intended to be limiting of the claims. To the contrary, the claims are intended to cover all alternatives, modifications, and equivalents.

(N,N-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate

Regulatory authorities worldwide require the amounts of impurities to be maintained at the lowest possible levels in pharmaceutical compositions and formulations. Hence there exists a need for stabilized compositions of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

If exposed to sufficient amounts of light or if sufficiently exposed to an oxidant, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is prone to a number of reactions such as oxidative stress and photodegradation, which gives rise to impurities. Two of several impurities which can be generated are tetramethyl cyclobutane-1,2,3,4-tetracarboxylate formed by photodegradation of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and dimethyl oxirane-2,3-dicarboxylate formed by oxidation of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In a first aspect, a dosage form is provided which comprises (a) a therapeutically effective amount of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; (b) one or more cyclobutane compounds of Formula (I):

and salts of any of the foregoing, wherein:

each of R¹ through R⁴ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl; and

wherein the one or more compounds of Formula (I) are present in a total combined amount of less than 2% by weight based on total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; and (c) a pharmaceutically acceptable vehicle.

In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of less than about 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (I) are present in a total combined amount of less than about 2% by weight based on total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a total combined amount of less than about 1% by weight based on total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

Compounds of Formula (I) include tetramethyl cyclobutane-1,2,3,4-tetracarboxylate, in which R¹ through R⁴ are all methyl; 3,4-bis(methoxycarbonyl)cyclobutane-1,2-dicarboxylic acid, in which R¹ and R² are each hydrogen and R³ and R⁴ are each methyl; 2,4-bis(methoxycarbonyl)cyclobutane-1,3-dicarboxylic acid, in which R¹ and R³ are each hydrogen and R² and R⁴ are each methyl; and cyclobutane-1,2,3,4-tetracarboxylic acid, in which R¹ through R⁴ are all hydrogen; as well as and salts of any of the foregoing. In some embodiments, the one or more compounds of Formula (I) is selected from the group consisting of 1,2-bis((N,N-diethylcarbamoyl)methoxycarbonyl)-3,4-bis(methoxycarbonyl)cyclobutane; 1,3-((N,N-diethylcarbamoyl)methoxycarbonyl)-2,4-bis(methoxycarbonyl)cyclobutane; 1-(N,N-diethylcarbamoyl)methoxycarbonyl-2-methoxycarbonylcyclobutane-3,4-dicarboxylic acid; 1,2-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-2,3-dicarboxylic acid; 1,3-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-2,4-dicarboxylic acid; 1,2-bis(methoxycarbonyl)cyclobutane-3,4-dicarboxylic acid; 1,3-bis(methoxycarbonyl)cyclobutane-2,4-dicarboylic acid; cyclobutane-1,2,3,4-tetracarboxylic acid; 1,2-((N,N-diethylcarbamoyl)methoxycarbonyl)-3-methoxycarbonylcyclobutane-4-carboxylic acid; 1,2-bis(methoxycarbonyl)cyclobutane-3,4-dicarboxylic acid; 1,2-bis(methoxycarbonyl)-3-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-4-carboxylic acid; 1,2-((N,N-diethylcarbamoyl)methoxycarbonyl)-3-(methoxycarbonyl)cyclobutane-4-carboxylic acid; 1-((N,N-diethylcarbamoyl)methoxycarbonyl)-2,3-bis(methoxycarbonyl)cyclobutane-4-carboxylic acid; 1-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-2,3,4-tricarboxylic acid; and 1-(methoxycarbonyl)cyclobutane-2,3,4-tricarboxylic acid; as well as salts of any of the foregoing.

In some embodiments, the isomers of compounds of Formula (I) include, 1R,2R,3R,4R-, 1S,2S,3S,4S-, 1R,2R,3S,4S-, or 1R,2S,3R,4S-isomers.

In some embodiments, the compounds of Formula (I) include 1R,2R,3S,4S-isomers.

In some embodiments, each of the one or more compounds of Formula (I) is present in an amount of less than about 0.3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (I) is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (I) is present in an amount of less than about 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (I) is present in an amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (I) is present in an amount of less than about 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (I) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (I) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (I) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (I) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (I) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In order to maintain a low content of photodegradant compounds of Formula (I) in a (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical composition or dosage form, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate active pharmaceutical ingredient as well as the dosage form should both be manufactured with minimal exposure to visible and/or UV light. Thus, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate powder should be exposed to visible and UV light levels below these limits in order to maintain the levels of photodegradant compounds of Formula (I) within acceptable ranges.

In order to reduce the impact of light, including natural light, ultra-violet light and near-UV light, on the stability of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate in a (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing dosage form, a barrier layer or coating can be applied to the dosage form. For oral dosage forms, examples include a coating on a (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing tablet or an opaque capsule containing (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioateparticles or pellets.

In some embodiments, the tablet or capsule coating is opaque and has a thickness of at least 10 μm. In some embodiments, the coating has a thickness of at least 300 μm. The coating may comprise a filler and/or a polymer. The coating may comprise an iron oxide colorant and other excipients. Alternatively, the coating may comprise a colorant (e.g., FD&C Yellow #6, Sunset Yellow, or FD&C Red #40 Allura Red) and other known coating excipients. Alternatively, the coating may comprise titanium dioxide, silicon dioxide or zinc dioxide and other known coating excipients.

The use of opaque plastic (e.g., high density polyethylene) pill bottles, e.g., with child-resistant screw caps, is one option to limit the amount of light exposure to a (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing dosage form. Blister packs, a term used for several types of pre-formed plastic pharmaceutical packaging, is another option. The primary component of a blister pack is a cavity or pocket made from a formable web, usually a thermoformed plastic. This usually has a backing of paperboard or a lidding seal of aluminum foil or plastic. The plastics can be made opaque, and/or with an anti-UV light coating, to limit the amount of light exposure to the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate dosage form.

In a second aspect, a pharmaceutical composition is provided which comprises (a) (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; and (b) one or more succinate compounds of Formula (II):

and salts of any of the foregoing, wherein:

each of R⁵ and R⁷ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl;

Y is chosen from O, S, NH and NR⁸;

R⁶ is chosen from hydrogen, lower alkyl and aryl; and

R⁸ is chosen from lower alkyl.

In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, each of R⁶ and R⁸ is independently unsubstituted alkyl. In some embodiments, each of R⁶ and R⁸ is independently alkyl, substituted with hydroxy.

In some embodiments, the one or more compounds of Formula (II) are present in a total combined amount of less than 3 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (II) are present in a total combined amount of less than 2 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (II) are present in a total combined amount of less than 1 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of less than about 3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of less than about 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds) of Formula (II) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (II) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

Compounds of Formula (II) include the following: (N,N-diethylcarbamoyl)methyl-methyl-hydroxysuccinate; methyl-hydroxysuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-hydroxysuccinic mono-acid; hydroxysuccinic acid; (N,N-diethylcarbamoyl)methyl-methyl-mercaptosuccinate; methylmercaptosuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-mercaptosuccinic mono-acid; mercaptosuccinic acid; (N,N-diethylcarbamoyl)methyl-methyl-aminosuccinate; methylaminosuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-aminosuccinic mono-acid; and aminosuccinic acid; as well as salts of any of the foregoing.

In some embodiments, each of the one or more compounds of Formula (II) is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (II) is present in an amount of less than about 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (II) is present in an amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (II) is present in an amount of less than about 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (II) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (II) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (II) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (II) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In another aspect, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain little or no alkanols or alcohols, thioalkanols or alkyl mercaptans, alkylamines, dialkylamines or any compound capable of acting as a nucleophile for addition to the double bond of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. For example, use of alcohols in a pharmaceutical composition can form the 2-alkoxy compound (Formula H, —Y—R⁶ is —O-alkyl) impurities into the formulation. Similarly, use of thioalcohols or mercaptans in a pharmaceutical composition can form the 2-thioalkoxy compound (Formula II, —Y—R⁶ is —S-alkyl) impurities into the formulation. Furthermore, use of primary amines in a pharmaceutical composition can form the 2-alkylamino compound (Formula II, —Y—R⁶ is —NH-alkyl) impurities into the formulation. Moreover, use of secondary amines in a pharmaceutical composition can form the 2-dialkylamino compound (Formula II, —Y—R⁶ is —N(alkyl)₂) impurities into the formulation.

Thus in some embodiments, the pharmaceutical compositions and dosage forms disclosed herein are substantially free of any alcohols, mercaptans, alkylamines, or dialkylamines. In some embodiments, the pharmaceutical compositions and dosage forms disclosed herein are substantially free of methanol, ethanol, methyl mercaptan, ethylamine, propylamine, butylamine, aspartame, diethanolamine, meglumine, monoethanolamine, or triethanolamine.

In a third aspect, a pharmaceutical composition is provided which comprises (a) (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; and (b) an oxirane compound of Formula (III):

and salts of any of the foregoing, wherein:

each of R⁹ and R¹⁰ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl; and

wherein the one or more compounds of Formula (III) are present in the dosage form in a combined total amount of less than 3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate

In a third aspect, a dosage form is provided which comprises (a) (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; and (b) an oxirane compound of Formula (III):

and salts of any of the foregoing, wherein:

each of R⁹ and R¹⁰ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl; and

wherein the one or more compounds of Formula (III) are present in the dosage form in a combined total amount of less than 3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate

In some embodiments of the pharmaceutical compositions and/or dosage forms, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is solid. In some embodiments of the pharmaceutical compositions and/or dosage forms, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is crystalline. In some embodiments of the pharmaceutical compositions and/or dosage forms, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is amorphous.

In some embodiments, the one or more compounds of Formula (III) are present in a total combined amount of less than 2 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (III) are present in a total combined amount of less than 1 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of less than about 3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of less than about 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds) of Formula (III) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (III) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl) methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments of the pharmaceutical compositions and/or dosage forms, the one or more compounds of Formula (III) include the following: dimethyl oxirane-2,3-dicarboxylate (compound (2)), in which both R⁹ and R¹⁰ are methyl; 3-(methoxycarbonyl)oxirane-2-carboxylic acid, in which R⁹ is methyl and R¹⁰ is hydrogen; oxirane-2,3-dicarboxylic acid, in which both R⁹ and R¹⁰ are hydrogen; and salts of any of the foregoing.

In some embodiments, each of the one or more compounds of Formula (III) is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (III) is present in an amount of less than about 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (III) is present in an amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (III) is present in an amount of less than about 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (III) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (III) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (III) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (III) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments of the pharmaceutical compositions and/or dosage forms, the one or more compounds of Formula (III) comprise dimethyl oxirane-2,3-dicarboxylate, and salts of any of the foregoing. In some embodiments of the pharmaceutical compositions and/or dosage forms, the one or more compounds of Formula (III) comprise dimethyl oxirane-2,3-dicarboxylate. In other embodiments, the one or more compounds of Formula (III) are selected from the group consisting of cis-(N,N-diethylcarbamoyl)methyl-methyl oxirane dicarboxylate; cis-(methoxycarbonyl)oxirane carboxylic mono-acid; cis-(N,N-diethylcarbamoyl)methoxycarbonyl oxirane carboxylic mono-acid; cis-oxirane 2,3-dicarboxylic acid; trans-(N,N-diethylcarbamoyl)methyl-methyl oxirane dicarboxylate; trans-(methoxycarbonyl)oxirane carboxylic mono-acid; trans-(N,N-diethylcarbamoyl)methoxycarbonyl oxirane carboxylic mono-acid; and trans-oxirane 2,3-dicarboxylic acid; as well as salts of any of the foregoing.

The toxicity of dimethyl oxirane-2,3-dicarboxylate was evaluated using Derek Nexus version 2.0 (Lhasa Ltd., Leeds, UK) which predicts toxicity based on a combination of published reports as well as compound structural characteristics and provides one of seven possible grades for toxicity: certain, probable, plausible, equivocal, doubted, improbable and impossible. Although there are no published reports testing the toxicity of compound (2), due to the epoxide portion of the molecule, the Derek Nexus database rates the toxicity of compound (2) as “plausible” meaning that the weight of evidence supports the proposition that the compound is toxic.

Compound (2) and its NMR spectrum are shown in Example 1 of Habich et al. U.S. Pat. No. 4,863,916, the disclosures of which are incorporated herein by reference. Using established analytical chemistry techniques, together with the disclosures in the Habich et al. patent, those skilled in the art can test pharmaceutical compositions and dosage forms for the presence of compound (2).

In another aspect, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain little or no polyvinylpyrrolidone (PVP) or polyethylene glycol (PEG). Use of polyvinylpyrrolidone (PVP) in a pharmaceutical composition can introduce peroxide impurities into the formulation since the PVP polymerization process involves the use of polymerization initiators such as peroxides, ozone, and hydrogen peroxides. Upon heat or light exposure, even trace amounts of peroxides can decompose into free radicals, which can powerfully catalyze photochemical reactions. Light-induced decomposition of polyoxyethylene chains of polyethylene glycols (PEG) or polysorbate surfactants can also result in the formation of hydrogen peroxides and/or peroxide-free radicals, which can promote degradation of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

Thus in some embodiments, the pharmaceutical compositions and dosage forms disclosed herein are substantially free of any polyvinylpyrrolidone, polyethylene glycol and/or polysorbate surfactant. In some embodiments, the pharmaceutical compositions and dosage forms disclosed herein contain no polyvinylpyrrolidone, polyethylene glycol and/or polysorbate surfactant.

In another aspect, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein may comprise an antioxidant. Suitable antioxidants include methyl paraben and propyl paraben and their salts (such as sodium, potassium), vitamin E, vitamin E TPGS, propyl gallate, sulfites, ascorbic acid, sodium benzoate, citric acid, cyclodextrins, peroxide scavengers, benzoic acid, ethylenediaminetetraacetic acid (EDTA) and salts thereof, chain terminators (e.g., thiols and phenols), butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) and the like, and combinations of any of the foregoing. In some embodiments, antioxidants such as butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) can be used. In some embodiments, the antioxidant may be present in an amount of about from 0.01 to 5.0%, and in some embodiments about from 0.5 to 2.0% by weight of the total pharmaceutical composition.

In another aspect, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein may comprise an antioxidant. Suitable free radical scavengers include tocopherol, naringenin and the like, and mixtures thereof.

In another aspect, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms comprise one or more vehicles or other excipients that are low in oxidizing agents such as hydrogen peroxide, formaldehydes and formic acid and low in metallic impurities such as iron ions (e.g., Fe⁺²) that have the capability to oxidize (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In a fourth aspect, a pharmaceutical composition is provided which comprises (a) (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; and (b) one or more succinate compounds of Formula (IV):

and salts of any of the foregoing, wherein:

each of R¹¹ and R¹² is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl.

In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (IV) are present in a total combined amount of less than 2 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (IV) are present in a total combined amount of less than 1 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of less than about 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IV) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

Compounds of Formula (IV) include the following: dimethyl succinate in which both R¹¹ and R¹² are methyl; 4-methoxy-4-oxobutanoic acid in which R¹¹ is methyl and R¹² is hydrogen; succinic acid in which both R¹¹ and R¹² are hydrogen; and salts of any of the foregoing. In some embodiments, the one or more compounds of Formula (IV) are selected from the group consisting of (N,N-diethylcarbamoyl)methyl-methyl-succinate; methylsuccinic mono-acid; ((N,N-diethylcarbamoyl)methyl)succinic mono-acid; and succinic acid; as well as any salts thereof.

In some embodiments, each of the one or more compounds of Formula (IV) is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IV) is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IV) is present in an amount of less than about 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IV) is present in an amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IV) is present in an amount of less than about 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (IV) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IV) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IV) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IV) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compound of Formula (IV) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In another aspect, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain little or no compound(s) capable of forming (N,N-diethylcarbamoyl) methyl, hydrogen or hydrogen radicals which will, in turn, facilitate the reduction of the double bond of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

Thus in some embodiments, the pharmaceutical compositions and dosage forms disclosed herein are substantially free of any compounds containing hydrazino group.

In a fifth aspect, a pharmaceutical composition is provided which comprises (a) (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; and (b) one or more succinate compounds of Formula (V):

and salts of any of the foregoing wherein:

each of R¹³ and R¹⁴ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl) methyl.

In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (V) are present in a total combined amount of less than 2 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (V) are present in a total combined amount of less than 1 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of less than about 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (V) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

Compounds of Formula (V) include the following: 2,3-dihydroxysuccinic acid dimethyl ester, in which both R¹³ and R¹⁴ are methyl; 2,3-dihydroxysuccinic acid monomethyl ester, in which R¹³ is methyl and R¹⁴ is hydrogen; 2,3-dihydroxysuccinic acid, in which both R¹³ and R¹⁴ are hydrogen; and salts of any of the foregoing. In some embodiments, the one or more compound of Formula (V) are selected from the group consisting of (N,N-diethylcarbamoyl)methyl-methyl-2,3-dihydroxysuccinate; methyl-2,3-dihydroxysuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-2,3-dihydroxysuccinic mono-acid; and 2,3-dihydroxysuccinic acid (tartaric acid); as well as any salts thereof.

In some embodiments, each of the one or more compounds of Formula (V) is present in an amount of less than about 0.3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (V) is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (V) is present in an amount of less than about 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (V) is present in an amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (V) is present in an amount of less than about 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (V) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (V) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (V) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (V) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (V) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In another aspect, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain little or no compound(s) capable of isomerizing the double bond of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In another aspect, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain antioxidants and/or free radical scavengers.

In a sixth aspect, a dosage form is provided which comprises (a) (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; and (b) one or more compounds of Formula (VI):

and salts of any of the foregoing, wherein:

Q is —O—, —S—, —NH—, —N(R¹⁷)— or C(R¹⁸)₂;

each of R¹⁵ and R¹⁶ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl;

R¹⁷ is (N,N-diethylcarbamoyl)methyl or alkyl; and

each R¹⁸ is independently hydrogen or alkyl; and

(c) a pharmaceutically acceptable vehicle.

In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (VI) are present in a total combined amount of less than 2 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (VI) are present in a total combined amount of less than 1 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of less than about 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VI) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

Compounds of Formula (VI) include the following compounds, wherein:

Q is —O—, and each R¹⁵ and R¹⁶ is methyl;

Q is —O—, and each R¹⁵ and R¹⁶ is H;

Q is —O—, and each R¹⁵ and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —O—, R¹⁵ is H, and R¹⁶ is methyl;

Q is —O—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —O—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —S—, and each of R¹⁵ and R¹⁶ is methyl;

Q is —S—, and each of R¹⁵ and R¹⁶ is H;

Q is —S—, and each of R¹⁵ and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —S—, R¹⁵ is H, and R¹⁶ is methyl;

Q is —S—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —S—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NH—, and each of R¹⁵ and R¹⁶ is methyl;

Q is —NH—, and each of R¹⁵ and R¹⁶ is H;

Q is —NH—, and each of R¹⁵ and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NH—, R¹⁵ is H, and R¹⁶ is methyl;

Q is —NH—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NH—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NMe-, and each of R¹⁵ and R¹⁶ is methyl;

Q is —NMe-, and each of R¹⁵ and R¹⁶ is H;

Q is —NMe-, and each of R¹⁵ and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NMe-, R¹⁵ is H, and R¹⁶ is methyl;

Q is —NMe-, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —NMe-, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —CH₂—, and each R¹⁵ and R¹⁶ is methyl;

Q is —CH₂—, and each R¹⁵ and R¹⁶ is H;

Q is —CH₂—, and each R¹⁵ and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

Q is —CH₂—, R¹⁵ is H, and R¹⁶ is methyl;

Q is —CH₂—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; and

Q is —CH₂—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl;

isomers of any of the foregoing compounds and salts of any of the foregoing compounds.

In some embodiments, each of the one or more compounds of Formula (VI) is present in an amount of less than about 0.3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VI) is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VI) is present in an amount of less than about 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VI) is present in an amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VI) is present in an amount of less than about 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (VI) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VI) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VI) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VI) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VI) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In another aspect, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain little or no compound(s) capable of reacting with (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioateto form Diels-Alder products.

For example, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate, which can act as dienophile, will react with cyclopentadiene, furan, thiofurans, or pyrroles, to form Diels-Alder cyclization products as shown below, where Q, R¹⁵ and R¹⁶ are as defined herein:

Thus in some embodiments, the pharmaceutical compositions and dosage forms disclosed herein are substantially free of any compounds containing furan, thiophene, and pyrrole moieties.

In a thirteenth aspect, a pharmaceutical composition is provided which comprises (a) (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; and (b) one or more maleate compounds of Formula (XIII):

and salts of any of the foregoing, wherein:

each of R³⁷ and R³⁸ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl.

In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (XIII) are present in a total combined amount of less than 2 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XIII) are present in a total combined amount of less than 1 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of less than about 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIII) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XIII) are selected from the group consisting of (N,N-diethylcarbamoyl)methyl methyl maleate, (N,N-diethylcarbamoyl)methyl maleic acid, bis(N,N-diethylcarbamoyl)methyl maleate, dimethyl maleate, methyl maleate, and maleic acid; as well as any salts thereof.

In some embodiments, each of the one or more compounds of Formula (XIII) is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIII) is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIII) is present in an amount of less than about 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIII) is present in an amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIII) is present in an amount of less than about 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (XIII) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIII) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIII) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIII) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compound of Formula (XIII) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In a fifteenth aspect, a pharmaceutical composition is provided which comprises (a) (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; and (b) one or more maleate compounds of Formula (XV):

and salts of any of the foregoing, wherein:

R⁴¹ is (N,N-diethylcarbamoyl)methyl; and

R⁴² is chosen from hydrogen, ethyl, and (N,N-diethylcarbamoyl)methyl.

In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (XV) are present in a total combined amount of less than 2 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XV) are present in a total combined amount of less than 1 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of less than about 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the (NA-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XV) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XV) are selected from the group consisting of (2E)-3-(((N,N-diethylcarbamoyl)methyl)oxycarbonyl)prop-2-enoic acid; (N,N-diethylcarbamoyl)methyl ethyl (2E)but-2-ene-1,4-dioate; and bis(N,N-diethylcarbamoyl)methyl(2E)but-2-ene-1,4-dioate; as well as any salts thereof.

In some embodiments, each of the one or more compounds of Formula (XV) is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XV) is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XV) is present in an amount of less than about 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XV) is present in an amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XV) is present in an amount of less than about 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (XV) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XV) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XV) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XV) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compound of Formula (XV) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In another aspect, a pharmaceutical composition is provided which comprises (a) (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate; and (b) N,N-diethyl-2-hydroxyacetamide:

and salts of any of the foregoing.

In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a total combined amount of less than 2 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a total combined amount of less than 1 wt % based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of less than about 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of less than about 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of less than about 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of less than about 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of less than about 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of less than about 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of less than about 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of less than about 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of less than about 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in an amount of less than about 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in an amount of less than about 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in an amount of less than about 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in an amount of less than about 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, N,N-diethyl-2-hydroxyacetamide is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

Methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate

Regulatory authorities worldwide require the amounts of impurities to be maintained at the lowest possible levels in pharmaceutical compositions and formulations. Hence there exists a need for stabilized compositions of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

If exposed to sufficient amounts of light or if sufficiently exposed to an oxidant, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is prone to a number of reactions such as oxidative stress and photodegradation, which gives rise to impurities. Two of several impurities which can be generated are tetramethyl cyclobutane-1,2,3,4-tetracarboxylate formed by photodegradation and transesterification of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and dimethyl oxirane-2,3-dicarboxylate formed by oxidation and transesterification of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In a seventh aspect, a dosage form is provided which comprises (a) a therapeutically effective amount of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; (b) one or more cyclobutane compounds of Formula (VII):

and salts of any of the foregoing, wherein:

each of R¹⁹ through R²² is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl; and

wherein the one or more compounds of Formula (VII) are present in a total combined amount of less than 2% by weight based on total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; and (c) a pharmaceutically acceptable vehicle.

In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of less than about 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (I) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (VII) are present in a total combined amount of less than about 2% by weight based on total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VII) are present in a total combined amount of less than about 1% by weight based on total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

Compounds of Formula (VII) include 1,2-bis(methoxycarbonyl)-3,4-bis(4-morpholin-4-ylbutoxycarbonyl)cyclobutane; 1,3-bis(methoycarbonyl)-2,4-bis(4-morpholin-4-ylbutoxycarbonyl)cyclobutane; 1-methoxycarbonyl-2-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-3,4-dicarboxylic acid; 1,2-bis(methoxycarbonyl)cyclobutane-2,3-dicarboxylic acid; 1,3-bis(methoxycarbonyl)cyclobutane-2,4-dicarboxylic acid; 1,2-bis-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-3,4-dicarboylic acid; 1,3-bis-(4-morpholin-4-ylbutyl)cyclobutane-2,4-dicarboylic acid; cyclobutane-1,2,3,4-tetracarboxylic acid; 1,2-bis(methoxycarbonyl)-3-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-4-carboxylic acid; 1,2-bis-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-3,4-dicarboxylic acid; 1,2-bis(4-morpholin-4-ylbutoxycarbonyl)-3-(methoxycarbonyl)cyclobutane-4-carboxylic acid; 1,2-bis(methoxycarbonyl)-3-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-4-carboxylic acid; 1-methoxycarbonyl-2,3-bis-(4-morpholin-4-ylbutoxycarbonyl) cyclobutane-4-carboxylic acid; 1-(methoxycarbonyl)cyclobutane-2,3,4-tricarboxylic acid; and 1-(4-morpholin-4-ylbutoxycarbonyl)cyclobutane-2,3,4-tricarboxylic acid; as well as salts of any of the foregoing.

In some embodiments, the isomers of compounds of Formula (VII) include, 1R,2R,3R,4R-, 1S,2S,3S,4S-, 1R,2R,3S,4S-, or 1R,2S,3R,4S-isomers.

In some embodiments, the compounds of Formula (VII) include 1R,2R,3S,4S-isomers.

In some embodiments, each of the one or more compounds of Formula (VII) is present in an amount of less than about 0.3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VII) is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VII) is present in an amount of less than about 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VII) is present in an amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VII) is present in an amount of less than about 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (VII) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VII) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VII) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VII) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VII) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In order to maintain a low content of photodegradant compounds of Formula (I) in a methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical composition or dosage form, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate active pharmaceutical ingredient as well as the dosage form should both be manufactured with minimal exposure to visible and/or UV light. Thus, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate powder should be exposed to visible and UV light levels below these limits in order to maintain the levels of photodegradant compounds of Formula (I) within acceptable ranges.

In order to reduce the impact of light, including natural light, ultra-violet light and near-UV light, on the stability of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate in a methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing dosage form, a barrier layer or coating can be applied to the dosage form. For oral dosage forms, examples include a coating on a methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing tablet or an opaque capsule containing methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate particles or pellets.

In some embodiments, the tablet or capsule coating is opaque and has a thickness of at least 10 μm. In some embodiments, the coating has a thickness of at least 300 μm. The coating may comprise a filler and/or a polymer. The coating may comprise an iron oxide colorant and other excipients. Alternatively, the coating may comprise a colorant (e.g., FD&C Yellow #6, Sunset Yellow, or FD&C Red #40 Allura Red) and other known coating excipients. Alternatively, the coating may comprise titanium dioxide, silicon dioxide or zinc dioxide and other known coating excipients.

The use of opaque plastic (e.g., high density polyethylene) pill bottles, e.g., with child-resistant screw caps, is one option to limit the amount of light exposure to a methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing dosage form. Blister packs, a term used for several types of pre-formed plastic pharmaceutical packaging, is another option. The primary component of a blister pack is a cavity or pocket made from a formable web, usually a thermoformed plastic. This usually has a backing of paperboard or a lidding seal of aluminum foil or plastic. The plastics can be made opaque, and/or with an anti-UV light coating, to limit the amount of light exposure to the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate dosage form.

In an eighth aspect, a pharmaceutical composition is provided which comprises (a) methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; and (b) one or more succinate compounds of Formula (VIII):

and salts of any of the foregoing, wherein:

each of R²³ and R²⁵ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl;

Y is chosen from O, S, NH and NR²⁶;

R²⁴ is chosen from hydrogen, lower alkyl, and aryl; and

R²⁶ is chosen from lower alkyl.

In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, each of R²⁴ and R²⁶ is unsubstituted alkyl. In some embodiments, each of R²⁴ and R²⁶ is independently alkyl, substituted with hydroxy.

In some embodiments, the one or more compounds of Formula (VIII) are present in a total combined amount of less than 3 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (VIII) are present in a total combined amount of less than 2 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (VIII) are present in a total combined amount of less than 1 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of less than about 3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of less than about 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds) of Formula (VIII) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (VIII) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

Compounds of Formula (VIII) include the following: methyl-(4-morpholin-4-ylbutyl)-hydroxysuccinate; (4-morpholin-4-ylbutyl)-hydroxysuccinic mono-acid; methylhydroxysuccinic mono-acid; hydroxysuccinic acid; methyl-(4-morpholin-4-ylbutyl)-mercaptosuccinate; (4-morpholin-4-ylbutyl)-mercaptosuccinic mono-acid; methyl-mercaptosuccinic mono-acid; mercaptosuccinic acid; methyl-(4-morpholin-4-ylbutyl)-aminosuccinate; (4-morpholin-4-ylbutyl)-aminosuccinic mono-acid; methylaminosuccinic mono-acid; and aminosuccinic acid; as well as salts of any of the foregoing.

In some embodiments, each of the one or more compounds of Formula (VIII) is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VIII) is present in an amount of less than about 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VIII) is present in an amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VIII) is present in an amount of less than about 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (VIII) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VIII) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VIII) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (VIII) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In another aspect, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain little or no alkanols or alcohols, thioalkanols or alkyl mercaptans, alkylamines, dialkylamines or any compound capable of acting as a nucleophile for addition to the double bond of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. For example, use of alcohols in a pharmaceutical composition can form the 2-alkoxy compound (Formula VIII, —Y—R²⁴ is —O-alkyl) impurities into the formulation. Similarly, use of thioalcohols or mercaptans in a pharmaceutical composition can form the 2-thioalkoxy compound (Formula VIII, —Y—R²⁴ is —S-alkyl) impurities into the formulation. Furthermore, use of primary amines in a pharmaceutical composition can form the 2-alkylamino compound (Formula VIII, —Y—R²⁴ is —NH-alkyl) impurities into the formulation. Moreover, use of secondary amines in a pharmaceutical composition can firm the 2-dialkylamino compound (Formula VIII, —Y—R²⁴ is —N(alkyl)₂) impurities into the formulation.

Thus in some embodiments, the pharmaceutical compositions and dosage forms disclosed herein are substantially free of any alcohols, mercaptans, alkylamines, or dialkylamines. In some embodiments, the pharmaceutical compositions and dosage forms disclosed herein are substantially free of methanol, ethanol, methyl mercaptan, ethylamine, propylamine, butylamine, aspartame, diethanolamine, meglumine, monoethanolamine, or triethanolamine.

In a ninth aspect, a pharmaceutical composition is provided which comprises (a) methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; and (b) an oxirane compound of Formula (IX):

and salts of any of the foregoing, wherein:

each of R²⁷ and R²⁸ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl; and

wherein the one or more compounds of Formula (IX) are present in the dosage form in a combined total amount of less than 3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In another aspect, a dosage form is provided which comprises (a) methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; and (b) an oxirane compound of Formula (IX):

and salts of any of the foregoing, wherein:

each of R²⁷ and R²⁸ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl; and

wherein the one or more compounds of Formula (IX) are present in the dosage form in a combined total amount of less than 3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments of the pharmaceutical compositions and/or dosage forms, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is solid. In some embodiments of the pharmaceutical compositions and/or dosage forms, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is crystalline. In some embodiments of the pharmaceutical compositions and/or dosage forms, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is amorphous.

In some embodiments, the one or more compounds of Formula (IX) are present in a total combined amount of less than 2 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (IX) are present in a total combined amount of less than 1 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of less than about 3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of less than about 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds) of Formula (IX) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (IX) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments of the pharmaceutical compositions and/or dosage forms, the one or more compounds of Formula (IX) include the following: dimethyl oxirane-2,3-dicarboxylate (compound (2)), in which both R²⁷ and R²⁸ are methyl; 3-(methoxycarbonyl)oxirane-2-carboxylic acid, in which R²⁷ is methyl and R²⁸ is hydrogen; oxirane-2,3-dicarboxylic acid, in which both R²⁷ and R²⁸ are hydrogen; and salts of any of the foregoing.

In some embodiments, each of the one or more compounds of Formula (IX) is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IX) is present in an amount of less than about 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IX) is present in an amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IX) is present in an amount of less than about 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (IX) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IX) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IX) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (IX) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments of the pharmaceutical compositions and/or dosage forms, the one or more compounds of Formula (IX) comprise dimethyl oxirane-2,3-dicarboxylate, and salts of any of the foregoing. In some embodiments of the pharmaceutical compositions and/or dosage forms, the one or more compounds of Formula (IX) comprise dimethyl oxirane-2,3-dicarboxylate. In other embodiments, the one or more compounds of Formula (IX) are selected from the group consisting of cis-(N,N-diethylcarbamoyl)methyl-methyl oxirane dicarboxylate; cis-(methoxycarbonyl)oxirane carboxylic mono-acid; cis-(N,N-diethylcarbamoyl)methoxycarbonyl oxirane carboxylic mono-acid; cis-oxirane 2,3-dicarboxylic acid; trans-(N,N-diethylcarbamoyl)methyl-methyl oxirane dicarboxylate; trans-(methoxycarbonyl)oxirane carboxylic mono-acid; trans-WA-diethylcarbamoyl)methoxycarbonyl oxirane carboxylic mono-acid; and trans-oxirane 2,3-dicarboxylic acid; as well as salts of any of the foregoing.

In another aspect, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain little or no polyvinylpyrrolidone (PVP) or polyethylene glycol (PEG). Use of polyvinylpyrrolidone (PVP) in a pharmaceutical composition can introduce peroxide impurities into the formulation since the PVP polymerization process involves the use of polymerization initiators such as peroxides, ozone, and hydrogen peroxides. Upon heat or light exposure, even trace amounts of peroxides can decompose into free radicals, which can powerfully catalyze photochemical reactions. Light-induced decomposition of polyoxyethylene chains of polyethylene glycols (PEG) or polysorbate surfactants can also result in the formation of hydrogen peroxides and/or peroxide-free radicals, which can promote degradation of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

Thus in some embodiments, the pharmaceutical compositions and dosage forms disclosed herein are substantially free of any polyvinylpyrrolidone, polyethylene glycol and/or polysorbate surfactant. In some embodiments, the pharmaceutical compositions and dosage forms disclosed herein contain no polyvinylpyrrolidone, polyethylene glycol and/or polysorbate surfactant.

In another aspect, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein may comprise an antioxidant. Suitable antioxidants include methyl paraben and propyl paraben and their salts (such as sodium, potassium), vitamin E, vitamin E TPGS, propyl gallate, sulfites, ascorbic acid, sodium benzoate, citric acid, cyclodextrins, peroxide scavengers, benzoic acid, ethylenediaminetetraacetic acid (EDTA) and salts thereof, chain terminators (e.g., thiols and phenols), butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) and the like, and combinations of any of the foregoing. In some embodiments, antioxidants such as butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) can be used. In some embodiments, the antioxidant may be present in an amount of about from 0.01 to 5.0%, and in some embodiments about from 0.5 to 2.0% by weight of the total pharmaceutical composition.

In another aspect, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein may comprise an antioxidant. Suitable free radical scavengers include tocopherol, naringenin and the like, and mixtures thereof.

In another aspect, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms comprise one or more vehicles or other excipients that are low in oxidizing agents such as hydrogen peroxide, formaldehydes and formic acid and low in metallic impurities such as iron ions (e.g., Fe⁺²) that have the capability to oxidize methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In a tenth aspect, a pharmaceutical composition is provided which comprises (a) methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; and (b) one or more succinate compounds of Formula (X):

and salts of any of the foregoing, wherein:

each of R²⁹ and R³⁰ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl.

In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (X) are present in a total combined amount of less than 2 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (X) are present in a total combined amount of less than 1 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of less than about 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (X) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

Compounds of Formula (X) include the following: dimethyl succinate in which both R²⁹ and R³⁰ are methyl; 4-methoxy-4-oxobutanoic acid in which R²⁹ is methyl and R³⁰ is hydrogen; succinic acid in which both R²⁹ and R³⁰ are hydrogen; and salts of any of the foregoing. In some embodiments, the one or more compounds of Formula (X) are selected from the group consisting of methyl-(4-morpholin-4-ylbutyl)-succinate; (4-morpholin-4-ylbutyl)-succinic mono-acid; methylsuccinic mono-acid; and succinic acid; as well as any salts of any of the foregoing.

In some embodiments, each of the one or more compounds of Formula (X) is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (X) is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (X) is present in an amount of less than about 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (X) is present in an amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (X) is present in an amount of less than about 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (X) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (X) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (X) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (X) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compound of Formula (X) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In another aspect, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain little or no compound(s) capable of forming (N,N-diethylcarbamoyl) methyl, hydrogen or hydrogen radicals which will, in turn, facilitate the reduction of the double bond of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

Thus in some embodiments, the pharmaceutical compositions and dosage forms disclosed herein are substantially free of any compounds containing hydrazino group.

In an eleventh aspect, a pharmaceutical composition is provided which comprises (a) methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; and (b) one or more succinate compounds of Formula (XI):

and salts of any of the foregoing wherein:

each of R³¹ and R³² is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl.

In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (XI) are present in a total combined amount of less than 2 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XI) are present in a total combined amount of less than 1 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of less than about 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XI) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

Compounds of Formula (XI) include the following: 2,3-dihydroxysuccinic acid dimethyl ester, in which both R¹³ and R¹⁴ are methyl; 2,3-dihydroxysuccinic acid monomethyl ester, in which R¹³ is methyl and R¹⁴ is hydrogen; 2,3-dihydroxysuccinic acid, in which both R¹³ and R¹⁴ are hydrogen; and salts of any of the foregoing. In some embodiments, the one or more compound of Formula (XI) are selected from the group consisting of methyl-(4-morpholin-4-ylbutyl)-2,3-dihydroxysuccinate; (4-morpholin-4-ylbutyl)-2,3-dihydroxysuccinic mono-acid; methyl-2,3-dihydroxysuccinic mono-acid; and 2,3-dihydroxysuccinic acid (tartaric acid); as well as any salts thereof.

In some embodiments, each of the one or more compounds of Formula (XI) is present in an amount of less than about 0.3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XI) is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XI) is present in an amount of less than about 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XI) is present in an amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XI) is present in an amount of less than about 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (XI) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XI) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XI) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XI) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XI) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In another aspect, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain little or no compound(s) capable of isomerizing the double bond of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In another aspect, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain antioxidants and/or free radical scavengers.

In a twelfth aspect, a dosage form is provided which comprises (a) methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; and (b) one or more compounds of Formula (XII):

and salts of any of the foregoing, wherein:

Q is —O—, —S—, —NH—, —N(R³⁵)—, or C(R³⁶)₂;

each of R³³ and R³⁴ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbomoyl)methyl;

R³⁵ is (N,N-diethylcarbamoyl)methyl or alkyl; and

each R³⁶ is independently hydrogen or alkyl; and

(c) a pharmaceutically acceptable vehicle.

In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (XII) are present in a total combined amount of less than 2 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XII) are present in a total combined amount of less than 1 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of less than about 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XII) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

Compounds of Formula (XII) include the following compounds, wherein:

Q is —O—, and each R³³ and R³⁴ is methyl;

Q is —O—, and each R³³ and R³⁴ is H;

Q is —O—, and each R³³ and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —O—, R³³ is H, and R³⁴ is methyl;

Q is —O—, R³³ is H, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —O—, R³³ is methyl, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —S—, and each of R³³ and R³⁴ is methyl;

Q is —S—, and each of R³³ and R³⁴ is H;

Q is —S—, and each of R³³ and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —S—, R³³ is H, and R³⁴ is methyl;

Q is —S—, R³³ is H, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —S—, R³³ is methyl, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NH—, and each of R³³ and R³⁴ is methyl;

Q is —NH—, and each of R³³ and R³⁴ is H;

Q is —NH—, and each of R³³ and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NH—, R³³ is H, and R³⁴ is methyl;

Q is —NH—, R³³ is H, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NH—, R³³ is methyl, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NMe-, and each of R³³ and R³⁴ is methyl;

Q is —NMe-, and each of R³³ and R³⁴ is H;

Q is —NMe-, and each of R³³ and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NMe-, R³³ is H, and R³⁴ is methyl;

Q is —NMe-, R³³ is H, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —NMe-, R³³ is methyl, and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —CH₂—, and each R³³ and R³⁴ is methyl;

Q is —CH₂—, and each R³³ and R³⁴ is H;

Q is —CH₂—, and each R³³ and R³⁴ is 4-morpholin-4-ylbutyl;

Q is —CH₂—, R³³ is H, and R³⁴ is methyl;

Q is —CH₂—, R³³ is H, and R³⁴ is 4-morpholin-4-ylbutyl; and

Q is —CH₂—, R³³ is methyl, and R³⁴ is 4-morpholin-4-ylbutyl;

isomers of any of the foregoing compounds and salts of any of the foregoing compounds.

In some embodiments, each of the one or more compounds of Formula (XII) is present in an amount of less than about 0.3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XII) is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XII) is present in an amount of less than about 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XII) is present in an amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XII) is present in an amount of less than about 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (XII) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XII) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XII) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XII) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XII) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In another aspect, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing pharmaceutical compositions and dosage forms disclosed herein contain little or no compound(s) capable of reacting with methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate to form Diels-Alder products.

For example, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate, which can act as dienophile, will react with cyclopentadiene, furan, thiofurans, or pyrroles, to form Diels-Alder cyclization products as shown below, where Q, R³³ and R³⁴ are as defined herein:

Thus in some embodiments; the pharmaceutical compositions and dosage forms disclosed herein are substantially free of any compounds containing furan, thiophene, and pyrrole moieties.

In a fourteenth aspect, a pharmaceutical composition is provided which comprises (a) methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; and (b) one or more maleate compounds of Formula (XIV):

and salts of any of the foregoing, wherein:

each of R³⁹ and R⁴⁹ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl.

In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (XIV) are present in a total combined amount of less than 2 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XIV) are present in a total combined amount of less than 1 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of less than about 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XIV) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XIV) are selected from the group consisting of 4-morpholin-4-ylbutyl methyl maleate, 4-morpholin-4-ylbutyl maleic acid, bis(4-morpholin-4-ylbutyl) maleate, dimethyl maleate, methyl maleate, and maleic acid; as well as any salts of any of the foregoing.

In some embodiments, each of the one or more compounds of Formula (XIV) is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIV) is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIV) is present in an amount of less than about 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIV) is present in an amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIV) is present in an amount of less than about 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (XIV) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIV) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIV) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XIV) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compound of Formula (XIV) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In a sixteenth aspect, a pharmaceutical composition is provided which comprises (a) methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; and (b) one or more maleate compounds of Formula (XVI):

salts of any of the foregoing, wherein:

R⁴³ is 4-morpholin-4-ylbutyl; and

R⁴⁴ is chosen from hydrogen, ethyl, and 4-morpholin-4-ylbutyl.

In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, the one or more compounds of Formula (XVI) are present in a total combined amount of less than 2 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XVI) are present in a total combined amount of less than 1 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of less than about 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of less than about 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of less than about 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of less than about 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of less than about 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of less than about 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of less than about 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of less than about 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of less than about 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the one or more compounds of Formula (XVI) are present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, the one or more compounds of Formula (XVI) are selected from the group consisting of (2E)-3-((4-morpholin-4-ylbutyl)oxycarbonyl)prop-2-enoic acid; ethyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-diate; and bis-(4-morpholin-4-ylbutyl) (2E)but-2-ene-1,4-dioate; as well as any salts of any of the foregoing.

In some embodiments, each of the one or more compounds of Formula (XVI) is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XVI) is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XVI) is present in an amount of less than about 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XVI) is present in an amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XVI) is present in an amount of less than about 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, each of the one or more compounds of Formula (XVI) is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XVI) is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XVI) is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compounds of Formula (XVI) is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, each of the one or more compound of Formula (XVI) is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In another aspect, a pharmaceutical composition is provided which comprises (a) methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate; and (b) 4-morpholin-4-ylbutan-1-ol, and salts of any of the foregoing.

In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in solid form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in crystalline form. In some embodiments, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is in amorphous form.

In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a total combined amount of less than 2 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a total combined amount of less than 1 wt % based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of less than about 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of less than about 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of less than about 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of less than about 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of less than about 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of less than about 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of less than about 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of less than about 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of less than about 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of about 0.001% to 2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of about 0.001% to 1.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of about 0.001% to 1.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of about 0.001% to 1.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of about 0.001% to 1.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of about 0.001% to 1.0% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of about 0.001% to 0.8% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of about 0.001% to 0.6% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of about 0.001% to 0.4% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in a combined total amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in an amount of less than about 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in an amount of less than about 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in an amount of less than about 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in an amount of less than about 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in an amount of about 0.001% to 0.3% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in an amount of about 0.001% to 0.2% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in an amount of about 0.001% to 0.15% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in an amount of about 0.001% to 0.1% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, 4-morpholin-4-ylbutan-1-ol is present in an amount of about 0.001% to 0.05% by weight based on the total weight of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

Pharmaceutical Compositions

Pharmaceutical compositions provided by the present disclosure may comprise a therapeutically effective amount of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate together with a suitable amount of one or more pharmaceutically acceptable vehicles so as to provide a composition for proper administration to a patient. Suitable pharmaceutical vehicles are described in the art.

In certain embodiments, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be incorporated into pharmaceutical compositions to be administered orally. Oral administration of such pharmaceutical compositions may result in uptake of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate throughout the intestine and entry into the systemic circulation. Such oral compositions may be prepared in a manner known in the pharmaceutical art and comprise (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and at least one pharmaceutically acceptable vehicle. Oral pharmaceutical compositions may include a therapeutically effective amount of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and a suitable amount of a pharmaceutically acceptable vehicle, so as to provide an appropriate form for administration to a patient.

(N,N-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be incorporated into pharmaceutical compositions to be administered by any other appropriate route of systemic administration including intramuscular, intravenous and oral.

Pharmaceutical compositions comprising (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be manufactured by means of conventional mixing, dissolving, granulating, dragee-making, levigating, emulsifying, encapsulating, entrapping, or lyophilizing processes. Pharmaceutical compositions may be formulated in a conventional manner using one or more physiologically acceptable carriers, diluents, excipients, or auxiliaries, which facilitate processing of the compound or crystalline forms thereof and one or more pharmaceutically acceptable vehicles into formulations that can be used pharmaceutically. Proper formulation is dependent upon the route of administration chosen. Pharmaceutical compositions provided by the present disclosure take the form of sustained-release formulations suitable for administration to a patient.

Pharmaceutical compositions provided by the present disclosure may be formulated in a unit dosage form. A unit dosage form refers to a physically discrete unit suitable as a unitary dose for patients undergoing treatment, with each unit containing a predetermined quantity of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate calculated to produce an intended therapeutic effect. A unit dosage form may be for a single daily dose, for administration 2 times per day, or one of multiple daily doses, e.g., 3 or more times per day. When multiple daily doses are used, a unit dosage form may be the same or different for each dose. One or more dosage forms may comprise a dose, which may be administered to a patient at a single point in time or during a time interval.

In certain embodiments, an oral dosage form provided by the present disclosure may be a controlled release dosage form. Controlled delivery technologies can improve the absorption of a drug in a particular region or regions of the gastrointestinal tract. Controlled drug delivery systems may be designed to deliver a drug in such a way that the drug level is maintained within a therapeutically effective window and effective and safe blood levels are maintained for a period as long as the system continues to deliver the drug with a particular release profile in the gastrointestinal tract. Controlled drug delivery may produce substantially constant blood levels of a drug over a period of time as compared to fluctuations observed with immediate release dosage forms. For some applications, maintaining a constant blood and tissue concentration throughout the course of therapy is the most desirable mode of treatment. Immediate release of drug may cause blood levels to peak above the level required to elicit a desired response, which may waste the drug and may cause or exacerbate toxic side effects. Controlled drug delivery can result in optimum therapy, and not only can reduce the frequency of dosing, but may also reduce the severity of side effects. Examples of controlled release dosage forms include dissolution controlled systems, diffusion controlled systems, ion exchange resins, osmotically controlled systems, erodible matrix systems, pH independent formulations, gastric retention systems, and the like.

An appropriate oral dosage form for a particular pharmaceutical composition provided by the present disclosure may depend, at least in part, on the gastrointestinal absorption properties of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and/or the stability of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate in the gastrointestinal tract, the pharmacokinetics of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and the intended therapeutic profile. An appropriate controlled release oral dosage form may be selected for a particular compound. For example, gastric retention oral dosage forms may be appropriate for compounds absorbed primarily from the upper gastrointestinal tract, and sustained release oral dosage forms may be appropriate for compounds absorbed primarily from the lower gastrointestinal tract. Certain compounds are absorbed primarily from the small intestine. In general, compounds traverse the length of the small intestine in about 3 to 5 hours. For compounds that are not easily absorbed by the small intestine or that do not dissolve readily, the window for active agent absorption in the small intestine may be too short to provide a desired therapeutic effect.

In certain embodiments, pharmaceutical compositions provided by the present disclosure may be practiced with dosage forms adapted to provide sustained release of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate upon oral administration. Sustained release oral dosage forms may be used to release drugs over a prolonged time period and are useful when it is desired that a drug or drug form be delivered to the lower gastrointestinal tract, including the colon. Sustained release oral dosage forms include any oral dosage form that maintains therapeutic concentrations of a drug in a biological fluid such as the plasma, blood, cerebrospinal fluid, or in a tissue or organ for a prolonged time period. Sustained release oral dosage forms include diffusion-controlled systems such as reservoir devices and matrix devices, dissolution-controlled systems, osmotic systems, and erosion-controlled systems. Sustained release oral dosage forms and methods of preparing the same are well known in the art.

In certain embodiments, pharmaceutical compositions provided by the present disclosure may include any enteric-coated sustained release oral dosage form for administering (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. In some embodiments, the enteric-coated oral dosage form is administered to a patient at a dosing frequency of three times per day. In some embodiments, the enteric-coated oral dosage form is administered to a patient at a dosing frequency of twice per day. In some embodiments, the enteric-coated oral dosage form is administered to a patient at a dosing frequency of once per day.

In certain embodiments, pharmaceutical compositions provided by the present disclosure may include any suitable dosage forms that achieve the above described in vitro release profiles. Such dosage forms may be any systemic dosage forms, including sustained release enteric-coated oral dosage forms and sustained release enteric-coated or non-enteric-coated oral dosage forms. Examples of suitable dosage forms are described herein. Those skilled in the formulation art can develop any number of acceptable dosage forms given the dosage forms described in the examples as a starting point.

An appropriate dose of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be determined according to any one of several well-established protocols. For example, animal studies such as studies using mice, rats, dogs, and/or monkeys may be used to determine an appropriate dose of a pharmaceutical compound. Results from animal studies may be extrapolated to determine doses for use in other species, such as for example, humans.

In other embodiments, pharmaceutical compositions provided by the present disclosure may comprise a therapeutically effective amount of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate together with a suitable amount of one or more pharmaceutically acceptable vehicles so as to provide a composition for proper administration to a patient. Suitable pharmaceutical vehicles are described in the art.

In certain embodiments, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be incorporated into pharmaceutical compositions to be administered orally. Oral administration of such pharmaceutical compositions may result in uptake of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate throughout the intestine and entry into the systemic circulation. Such oral compositions may be prepared in a manner known in the pharmaceutical art and comprise methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and at least one pharmaceutically acceptable vehicle. Oral pharmaceutical compositions may include a therapeutically effective amount of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and a suitable amount of a pharmaceutically acceptable vehicle, so as to provide an appropriate form for administration to a patient.

Methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be incorporated into pharmaceutical compositions to be administered by any other appropriate route of systemic administration including intramuscular, intravenous and oral.

Pharmaceutical compositions comprising methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be manufactured by means of conventional mixing, dissolving, granulating, dragee-making, levigating, emulsifying, encapsulating, entrapping, or lyophilizing processes. Pharmaceutical compositions may be formulated in a conventional manner using one or more physiologically acceptable carriers, diluents, excipients, or auxiliaries, which facilitate processing of the compound or crystalline forms thereof and one or more pharmaceutically acceptable vehicles into formulations that can be used pharmaceutically. Proper formulation is dependent upon the route of administration chosen. Pharmaceutical compositions provided by the present disclosure take the form of sustained-release formulations suitable for administration to a patient.

Pharmaceutical compositions provided by the present disclosure may be formulated in a unit dosage form. A unit dosage form refers to a physically discrete unit suitable as a unitary dose for patients undergoing treatment, with each unit containing a predetermined quantity of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate calculated to produce an intended therapeutic effect. A unit dosage form may be for a single daily dose, for administration 2 times per day, or one of multiple daily doses, e.g., 3 or more times per day. When multiple daily doses are used, a unit dosage form may be the same or different for each dose. One or more dosage forms may comprise a dose, which may be administered to a patient at a single point in time or during a time interval.

In certain embodiments, an oral dosage form provided by the present disclosure may be a controlled release dosage form. Controlled delivery technologies can improve the absorption of a drug in a particular region or regions of the gastrointestinal tract. Controlled drug delivery systems may be designed to deliver a drug in such a way that the drug level is maintained within a therapeutically effective window and effective and safe blood levels are maintained for a period as long as the system continues to deliver the drug with a particular release profile in the gastrointestinal tract. Controlled drug delivery may produce substantially constant blood levels of a drug over a period of time as compared to fluctuations observed with immediate release dosage forms. For some applications, maintaining a constant blood and tissue concentration throughout the course of therapy is the most desirable mode of treatment. Immediate release of drug may cause blood levels to peak above the level required to elicit a desired response, which may waste the drug and may cause or exacerbate toxic side effects. Controlled drug delivery can result in optimum therapy, and not only can reduce the frequency of dosing, but may also reduce the severity of side effects. Examples of controlled release dosage forms include dissolution controlled systems, diffusion controlled systems, ion exchange resins, osmotically controlled systems, erodible matrix systems, pH independent formulations, gastric retention systems, and the like.

An appropriate oral dosage form for a particular pharmaceutical composition provided by the present disclosure may depend, at least in part, on the gastrointestinal absorption properties of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and/or the stability of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate in the gastrointestinal tract, the pharmacokinetics of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and the intended therapeutic profile. An appropriate controlled release oral dosage form may be selected for a particular compound. For example, gastric retention oral dosage forms may be appropriate for compounds absorbed primarily from the upper gastrointestinal tract, and sustained release oral dosage forms may be appropriate for compounds absorbed primarily from the lower gastrointestinal tract. Certain compounds are absorbed primarily from the small intestine. In general, compounds traverse the length of the small intestine in about 3 to 5 hours. For compounds that are not easily absorbed by the small intestine or that do not dissolve readily, the window for active agent absorption in the small intestine may be too short to provide a desired therapeutic effect.

In certain embodiments, pharmaceutical compositions provided by the present disclosure may be practiced with dosage forms adapted to provide sustained release of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate upon oral administration. Sustained release oral dosage forms may be used to release drugs over a prolonged time period and are useful when it is desired that a drug or drug form be delivered to the lower gastrointestinal tract, including the colon. Sustained release oral dosage forms include any oral dosage form that maintains therapeutic concentrations of a drug in a biological fluid such as the plasma, blood, cerebrospinal fluid, or in a tissue or organ for a prolonged time period. Sustained release oral dosage forms include diffusion-controlled systems such as reservoir devices and matrix devices, dissolution-controlled systems, osmotic systems, and erosion-controlled systems. Sustained release oral dosage forms and methods of preparing the same are well known in the art.

In certain embodiments, pharmaceutical compositions provided by the present disclosure may include any enteric-coated sustained release oral dosage form for administering methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. In some embodiments, the enteric-coated oral dosage form is administered to a patient at a dosing frequency of three times per day. In some embodiments, the enteric-coated oral dosage form is administered to a patient at a dosing frequency of twice per day. In some embodiments, the enteric-coated oral dosage form is administered to a patient at a dosing frequency of once per day.

In certain embodiments, pharmaceutical compositions provided by the present disclosure may include any suitable dosage forms that achieve the above described in vitro release profiles. Such dosage forms may be any systemic dosage forms, including sustained release enteric-coated oral dosage forms and sustained release enteric-coated or non-enteric-coated oral dosage forms. Examples of suitable dosage forms are described herein. Those skilled in the formulation art can develop any number of acceptable dosage forms given the dosage forms described in the examples as a starting point.

An appropriate dose of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be determined according to any one of several well-established protocols. For example, animal studies such as studies using mice, rats, dogs, and/or monkeys may be used to determine an appropriate dose of a pharmaceutical compound. Results from animal studies may be extrapolated to determine doses for use in other species, such as for example, humans.

Uses

The methods and compositions disclosed herein can be used to treat patients suffering from diseases, disorders, conditions, and symptoms for which (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and/or other fumaric acid esters are known to provide, or are later found to provide, therapeutic benefit. (N,N-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate can be used to treat a disease chosen from adrenal leukodystrophy, AGE-induced genome damage, Alexander Disease, Alper's Disease, Alzheimer's disease, amyotrophic lateral sclerosis, angina pectoris, arthritis, asthma, balo concentric sclerosis, Canavan disease, cardiac insufficiency including left ventricular insufficiency, central nervous system vasculitis, Charcott-Marie-Tooth Disease, childhood ataxia with central nervous system hypomyelination, chronic idiopathic peripheral neuropathy, chronic obstructive pulmonary disease, Crohn's disease, diabetic retinopathy, graft versus host disease, hepatitis C viral infection, herpes simplex viral infection, human immunodeficiency viral infection, Huntington's disease, irritable bowel disorder, ischemia, Krabbe Disease, lichen planus, macular degeneration, mitochondrial encephalomyopathy, monomelic amyotrophy, multiple sclerosis, myocardial infarction, neurodegeneration with brain iron accumulation, neuromyelitis optica, neurosarcoidosis, NF-κB mediated diseases, optic neuritis, paraneoplastic syndromes, Parkinson's disease, Pelizaeus-Merzbacher disease, primary lateral sclerosis, progressive supranuclear palsy, psoriasis, reperfusion injury, retinopathia pigmentosa, Schilder's Disease, subacute necrotizing myelopathy, Susac's syndrome, transplantation rejection, transverse myelitis, a tumor, ulcerative colitis and Zellweger's syndrome.

Methods of treating a disease in a patient provided by the present disclosure comprise administering to a patient in need of such treatment a therapeutically effective amount of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. These methods and pharmaceutical compositions provide therapeutic or prophylactic plasma and/or blood concentrations of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate following administration to a patient. (N,N-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be administered in an amount and using a dosing schedule as appropriate for treatment of a particular disease. Daily doses of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may range from about 0.01 mg/kg to about 50 mg/kg, from about 0.1 mg/kg to about 50 mg/kg, from about 1 mg/kg to about 50 mg/kg, and in certain embodiments, from about 5 mg/kg to about 25 mg/kg. In certain embodiments, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be administered at a dose over time from about 1 mg to about 5 g per day, from about 10 mg to about 4 g per day, in certain embodiments from about 20 mg to about 2 g per day, in certain embodiments from about 100 mg to about 1 g per day, in certain embodiments from about 200 mg to about 800 mg per day, in certain embodiments from about 300 mg to about 600 mg per day, and in certain embodiments from about 400 mg to about 500 mg per day. An appropriate dose of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be determined based on several factors, including, for example, the body weight and/or condition of the patient being treated, the severity of the disease being treated, the incidence and/or severity of side effects, the manner of administration, and the judgment of the prescribing physician. Appropriate dose ranges may be determined by methods known to those skilled in the art.

(N,N-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be assayed in vitro and in vivo for the desired therapeutic or prophylactic activity prior to use in humans. In vivo assays, for example using appropriate animal models, may also be used to determine whether administration of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is therapeutically effective.

In certain embodiments, a therapeutically effective dose of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may provide therapeutic benefit without causing substantial toxicity including adverse side effects. Toxicity of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and/or metabolites thereof may be determined as described herein and/or by using standard pharmaceutical procedures and may be ascertained by those skilled in the art. The dose ratio between toxic and therapeutic effect is the therapeutic index. A dose of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be within a range capable of establishing and maintaining a therapeutically effective circulating plasma and/or blood concentration of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate that exhibits little or no toxicity.

(N,N-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate administration may be used to treat a disease chosen from adrenal leukodystrophy, AGE-induced genome damage, Alexander Disease, Alper's Disease, Alzheimer's disease, amyotrophic lateral sclerosis, angina pectoris, arthritis, asthma, balo concentric sclerosis, Canavan disease, cardiac insufficiency including left ventricular insufficiency, central nervous system vasculitis, Charcott-Marie-Tooth Disease, childhood ataxia with central nervous system hypomyelination, chronic idiopathic peripheral neuropathy, chronic obstructive pulmonary disease, Crohn's disease, diabetic retinopathy, graft versus host disease, hepatitis C viral infection, herpes simplex viral infection, human immunodeficiency viral infection, Huntington's disease, irritable bowel disorder, ischemia, Krabbe Disease, lichen planus, macular degeneration, mitochondrial encephalomyopathy, monomelic amyotrophy, multiple sclerosis, myocardial infarction, neurodegeneration with brain iron accumulation, neuromyelitis optica, neurosarcoidosis, NF-κB mediated diseases, optic neuritis, paraneoplastic syndromes, Parkinson's disease, Pelizaeus-Merzbacher disease, primary lateral sclerosis, progressive supranuclear palsy, psoriasis, reperfusion injury, retinopathia pigmentosa, Schilder's Disease, subacute necrotizing myelopathy, Susac's syndrome, transplantation rejection, transverse myelitis, a tumor, ulcerative colitis, and Zellweger's syndrome. The underlying etiology of any of the foregoing diseases being treated may have a multiplicity of origins. Further, in certain embodiments, a therapeutically effective amount of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be administered to a patient, such as a human, as a preventative measure against the foregoing diseases and disorders. Thus, a therapeutically effective amount of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be administered as a preventative measure to a patient having a predisposition for and/or history of adrenal leukodystrophy, AGE-induced genome damage, Alexander Disease, Alper's Disease, Alzheimer's disease, amyotrophic lateral sclerosis, angina pectoris, arthritis, asthma, balo concentric sclerosis, Canavan disease, cardiac insufficiency including left ventricular insufficiency, central nervous system vasculitis, Charcott-Marie-Tooth Disease, childhood ataxia with central nervous system hypomyelination, chronic idiopathic peripheral neuropathy, chronic obstructive pulmonary disease, Crohn's disease, diabetic retinopathy, graft versus host disease, hepatitis C viral infection, herpes simplex viral infection, human immunodeficiency viral infection, Huntington's disease, irritable bowel disorder, ischemia, Krabbe Disease, lichen planus, macular degeneration, mitochondrial encephalomyopathy, monomelic amyotrophy, multiple sclerosis, myocardial infarction, neurodegeneration with brain iron accumulation, neuromyelitis optica, neurosarcoidosis, NF-κB mediated diseases, optic neuritis, paraneoplastic syndromes, Parkinson's disease, Pelizaeus-Merzbacher disease, primary lateral sclerosis, progressive supranuclear palsy, psoriasis, reperfusion injury, retinopathia pigmentosa, Schilder's Disease, subacute necrotizing myelopathy, Susac's syndrome, transplantation rejection, transverse myelitis, a tumor, ulcerative colitis, and/or Zellweger's syndrome.

In other embodiments, the methods and compositions disclosed herein can be used to treat patients suffering from diseases, disorders, conditions, and symptoms for which methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and/or other fumaric acid esters are known to provide, or are later found to provide, therapeutic benefit. Methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate can be used to treat a disease chosen from adrenal leukodystrophy, AGE-induced genome damage, Alexander Disease, Alper's Disease, Alzheimer's disease, amyotrophic lateral sclerosis, angina pectoris, arthritis, asthma, balo concentric sclerosis, Canavan disease, cardiac insufficiency including left ventricular insufficiency, central nervous system vasculitis, Charcott-Marie-Tooth Disease, childhood ataxia with central nervous system hypomyelination, chronic idiopathic peripheral neuropathy, chronic obstructive pulmonary disease, Crohn's disease, diabetic retinopathy, graft versus host disease, hepatitis C viral infection, herpes simplex viral infection, human immunodeficiency viral infection, Huntington's disease, irritable bowel disorder, ischemia, Krabbe Disease, lichen planus, macular degeneration, mitochondrial encephalomyopathy, monomelic amyotrophy, multiple sclerosis, myocardial infarction, neurodegeneration with brain iron accumulation, neuromyelitis optica, neurosarcoidosis, NF-κB mediated diseases, optic neuritis, paraneoplastic syndromes, Parkinson's disease, Pelizaeus-Merzbacher disease, primary lateral sclerosis, progressive supranuclear palsy, psoriasis, reperfusion injury, retinopathia pigmentosa, Schilder's Disease, subacute necrotizing myelopathy, Susac's syndrome, transplantation rejection, transverse myelitis, a tumor, ulcerative colitis, and Zellweger's syndrome.

Methods of treating a disease in a patient provided by the present disclosure comprise administering to a patient in need of such treatment a therapeutically effective amount of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. These methods and pharmaceutical compositions provide therapeutic or prophylactic plasma and/or blood concentrations of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate following administration to a patient. Methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be administered in an amount and using a dosing schedule as appropriate for treatment of a particular disease. Daily doses of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may range from about 0.01 mg/kg to about 50 mg/kg, from about 0.1 mg/kg to about 50 mg/kg, from about 1 mg/kg to about 50 mg/kg, and in certain embodiments, from about 5 mg/kg to about 25 mg/kg. In certain embodiments, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be administered at a dose over time from about 1 mg to about 5 g per day, from about 10 mg to about 4 g per day, in certain embodiments from about 20 mg to about 2 g per day, in certain embodiments from about 100 mg to about 1 g per day, in certain embodiments from about 200 mg to about 800 mg per day, in certain embodiments from about 300 mg to about 600 mg per day, and in certain embodiments from about 400 mg to about 500 mg per day. An appropriate dose of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be determined based on several factors, including, for example, the body weight and/or condition of the patient being treated, the severity of the disease being treated, the incidence and/or severity of side effects, the manner of administration, and the judgment of the prescribing physician. Appropriate dose ranges may be determined by methods known to those skilled in the art.

Methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be assayed in vitro and in vivo for the desired therapeutic or prophylactic activity prior to use in humans. In vivo assays, for example using appropriate animal models, may also be used to determine whether administration of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is therapeutically effective.

In certain embodiments, a therapeutically effective dose of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may provide therapeutic benefit without causing substantial toxicity including adverse side effects. Toxicity of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and/or metabolites thereof may be determined as described herein and/or by using standard pharmaceutical procedures and may be ascertained by those skilled in the art. The dose ratio between toxic and therapeutic effect is the therapeutic index. A dose of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be within a range capable of establishing and maintaining a therapeutically effective circulating plasma and/or blood concentration of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate that exhibits little or no toxicity.

Methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate administration may be used to treat a disease chosen from adrenal leukodystrophy, AGE-induced genome damage, Alexander Disease, Alper's Disease, Alzheimer's disease, amyotrophic lateral sclerosis, angina pectoris, arthritis, asthma, balo concentric sclerosis, Canavan disease, cardiac insufficiency including left ventricular insufficiency, central nervous system vasculitis, Charcott-Marie-Tooth Disease, childhood ataxia with central nervous system hypomyelination, chronic idiopathic peripheral neuropathy, chronic obstructive pulmonary disease, Crohn's disease, diabetic retinopathy, graft versus host disease, hepatitis C viral infection, herpes simplex viral infection, human immunodeficiency viral infection, Huntington's disease, irritable bowel disorder, ischemia, Krabbe Disease, lichen planus, macular degeneration, mitochondrial encephalomyopathy, monomelic amyotrophy, multiple sclerosis, myocardial infarction, neurodegeneration with brain iron accumulation, neuromyelitis optica, neurosarcoidosis, NF-κB mediated diseases, optic neuritis, paraneoplastic syndromes, Parkinson's disease, Pelizaeus-Merzbacher disease, primary lateral sclerosis, progressive supranuclear palsy, psoriasis, reperfusion injury, retinopathia pigmentosa, Schilder's Disease, subacute necrotizing myelopathy, Susac's syndrome, transplantation rejection, transverse myelitis, a tumor, ulcerative colitis and Zellweger's syndrome. The underlying etiology of any of the foregoing diseases being treated may have a multiplicity of origins. Further, in certain embodiments, a therapeutically effective amount of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be administered to a patient, such as a human, as a preventative measure against the foregoing diseases and disorders. Thus, a therapeutically effective amount of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be administered as a preventative measure to a patient having a predisposition for and/or history of adrenal leukodystrophy, AGE-induced genome damage, Alexander Disease, Alper's Disease, Alzheimer's disease, amyotrophic lateral sclerosis, angina pectoris, arthritis, asthma, balo concentric sclerosis, Canavan disease, cardiac insufficiency including left ventricular insufficiency, central nervous system vasculitis, Charcott-Marie-Tooth Disease, childhood ataxia with central nervous system hypomyelination, chronic idiopathic peripheral neuropathy, chronic obstructive pulmonary disease, Crohn's disease, diabetic retinopathy, graft versus host disease, hepatitis C viral infection, herpes simplex viral infection, human immunodeficiency viral infection, Huntington's disease, irritable bowel disorder, ischemia, Krabbe Disease, lichen planus, macular degeneration, mitochondrial encephalomyopathy, monomelic amyotrophy, multiple sclerosis, myocardial infarction, neurodegeneration with brain iron accumulation, neuromyelitis optica, neurosarcoidosis, NF-κB mediated diseases, optic neuritis, paraneoplastic syndromes, Parkinson's disease, Pelizaeus-Merzbacher disease, primary lateral sclerosis, progressive supranuclear palsy, psoriasis, reperfusion injury, retinopathia pigmentosa, Schilder's Disease, subacute necrotizing myelopathy, Susac's syndrome, transplantation rejection, transverse myelitis, a tumor, ulcerative colitis, and/or Zellweger's syndrome.

Administration

(N,N-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and pharmaceutical compositions thereof may be administered orally or by any other appropriate route suitable for systemic or local administration. For example, systemic administration can be by infusion or bolus injection, by absorption through epithelial or mucocutaneous linings (e.g., oral mucosa, rectal, and intestinal mucosa, etc.). Other suitable routes of systemic administration include, but are not limited to, intradermal, intramuscular, intraperitoneal, intravenous, subcutaneous, intranasal, epidural, oral, sublingual and inhalation. Local administration can be topical (e.g., by applying a (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate-containing cream or lotion to an effected area of skin), or by localized injection into an effected organ (e.g., the eyeball).

The amount of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate that will be effective in the treatment of a disease in a patient will depend, in part, on the nature of the condition and can be determined by standard clinical techniques known in the art. In addition, in vitro or in vivo assays may be employed to help identify optimal dosage ranges. A therapeutically effective amount of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate to be administered may also depend on, among other factors, the subject being treated, the weight of the subject, the severity of the disease, the manner of administration, and the judgment of the prescribing physician.

For systemic administration, a therapeutically effective dose may be estimated initially from in vitro assays. For example, a dose may be formulated in animal models to achieve a beneficial circulating composition concentration range. Initial doses may also be estimated from in vivo data, e.g., animal models, using techniques that are known in the art. Such information may be used to more accurately determine useful doses in humans. One having ordinary skill in the art may optimize administration to humans based on animal data.

A dose may be administered in a single dosage form or in multiple dosage forms. When multiple dosage forms are used the amount of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate contained within each dosage form may be the same or different. The amount of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate contained in a dose may depend on the route of administration and whether the disease in a patient is effectively treated by acute, chronic, or a combination of acute and chronic administration.

In certain embodiments an administered dose is less than a toxic dose. Toxicity of the compositions described herein may be determined by standard pharmaceutical procedures in cell cultures or experimental animals, e.g., by determining the LD₅₀ (the dose lethal to 50% of the population) or the LD₁₀₀ (the dose lethal to 100% of the population). The dose ratio between toxic and therapeutic effect is the therapeutic index. In certain embodiments, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may exhibit a high therapeutic index. The data obtained from these cell culture assays and animal studies may be used in formulating a dosage range that is not toxic for use in humans. A dose of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate provided by the present disclosure may be within a range of circulating concentrations in for example the blood, plasma, or central nervous system, that include the effective dose and that exhibits little or no toxicity. A dose may vary within this range depending upon the dosage form employed and the route of administration utilized. In certain embodiments, an escalating dose may be administered.

In some embodiments, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and pharmaceutical compositions thereof may be administered orally or by any other appropriate route suitable for systemic or local administration. For example, systemic administration can be by infusion or bolus injection, by absorption through epithelial or mucocutaneous linings (e.g., oral mucosa, rectal, and intestinal mucosa, etc.). Other suitable routes of systemic administration include, but are not limited to, intradermal, intramuscular, intraperitoneal, intravenous, subcutaneous, intranasal, epidural, oral, sublingual and inhalation. Local administration can be topical (e.g., by applying a methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate-containing cream or lotion to an effected area of skin), or by localized injection into an effected organ (e.g., the eyeball).

The amount of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate that will be effective in the treatment of a disease in a patient will depend, in part, on the nature of the condition and can be determined by standard clinical techniques known in the art. In addition, in vitro or in vivo assays may be employed to help identify optimal dosage ranges. A therapeutically effective amount of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate to be administered may also depend on, among other factors, the subject being treated, the weight of the subject, the severity of the disease, the manner of administration, and the judgment of the prescribing physician.

For systemic administration, a therapeutically effective dose may be estimated initially from in vitro assays. For example, a dose may be formulated in animal models to achieve a beneficial circulating composition concentration range. Initial doses may also be estimated from in vivo data, e.g., animal models, using techniques that are known in the art. Such information may be used to more accurately determine useful doses in humans. One having ordinary skill in the art may optimize administration to humans based on animal data.

A dose may be administered in a single dosage form or in multiple dosage forms. When multiple dosage forms are used the amount of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate contained within each dosage form may be the same or different. The amount of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate contained in a dose may depend on the route of administration and whether the disease in a patient is effectively treated by acute, chronic, or a combination of acute and chronic administration.

In certain embodiments an administered dose is less than a toxic dose. Toxicity of the compositions described herein may be determined by standard pharmaceutical procedures in cell cultures or experimental animals, e.g., by determining the LD₅₀ (the dose lethal to 50% of the population) or the LD₁₀₀ (the dose lethal to 100% of the population). The dose ratio between toxic and therapeutic effect is the therapeutic index. In certain embodiments, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may exhibit a high therapeutic index. The data obtained from these cell culture assays and animal studies may be used in formulating a dosage range that is not toxic for use in humans. A dose of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate provided by the present disclosure may be within a range of circulating concentrations in for example the blood, plasma, or central nervous system, that include the effective dose and that exhibits little or no toxicity. A dose may vary within this range depending upon the dosage form employed and the route of administration utilized. In certain embodiments, an escalating dose may be administered.

Combination Therapy

Methods provided by the present disclosure further comprise administering one or more pharmaceutically active compounds in addition to (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. Such compounds may be provided to treat the same disease or a different disease than the disease being treated with the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In certain embodiments, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be used in combination with DMF.

In certain embodiments, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be used in combination with MMF.

In certain embodiments, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be used in combination with methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In certain embodiments, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be used in combination with at least one other therapeutic agent. In certain embodiments, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be administered to a patient together with another compound for treating diseases and conditions including: adrenal leukodystrophy, Alexander Disease, Alper's Disease, balo concentric sclerosis, Canavan disease, central nervous system vasculitis, Charcott-Marie-Tooth Disease, childhood ataxia with central nervous system hypomyelination, diabetic retinopathy, graft versus host disease, hepatitis C viral infection, herpes simplex viral infection, human immunodeficiency viral infection, Krabbe Disease, lichen planus, macular degeneration, monomelic amyotrophy, neurodegeneration with brain iron accumulation, neuromyelitis optica, neurosarcoidosis, optic neuritis, paraneoplastic syndromes, Pelizaeus-Merzbacher disease, primary lateral sclerosis, progressive supranuclear palsy, Schilder's Disease, subacute necrotizing myelopathy, Susac's syndrome, transverse myelitis, a tumor, and Zellweger's syndrome.

(N,N-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and the at least one other therapeutic agent may act additively or, and in certain embodiments, synergistically. The at least one additional therapeutic agent may be included in the same dosage form as (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate or may be provided in a separate dosage form. Methods provided by the present disclosure can further include, in addition to administering (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate, administering one or more therapeutic agents effective for treating the same or different disease than the disease being treated by (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. Methods provided by the present disclosure include administration of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and one or more other therapeutic agents provided that the combined administration does not inhibit the therapeutic efficacy of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and/or does not typically produce significant and/or substantial adverse combination effects.

In certain embodiments, dosage forms comprising (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be administered concurrently with the administration of another therapeutic agent, which may be part of the same dosage form as, or in a different dosage form than that comprising (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be administered prior or subsequent to administration of another therapeutic agent. In certain embodiments, the combination therapy may comprise alternating between administering (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and a composition comprising another therapeutic agent, e.g., to minimize adverse drug effects associated with a particular drug. When (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate is administered concurrently with another therapeutic agent that potentially may produce an adverse drug effect including, but not limited to, toxicity, the other therapeutic agent may advantageously be administered at a dose that falls below the threshold at which the adverse drug reaction is elicited.

In certain embodiments, dosage forms comprising (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be administered with one or more substances to enhance, modulate and/or control release, bioavailability, therapeutic efficacy, therapeutic potency, stability, and the like of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate. For example, to enhance the therapeutic efficacy of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate, the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be co-administered with or a dosage form comprising (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate and one or more active agents to increase the absorption or diffusion of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate from the gastrointestinal tract to the systemic circulation, or to inhibit degradation of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate in the blood of a patient. In certain embodiments, (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate may be co-administered with an active agent having pharmacological effects that enhance the therapeutic efficacy of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In other embodiments, methods provided by the present disclosure further comprise administering one or more pharmaceutically active compounds in addition to methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. Such compounds may be provided to treat the same disease or a different disease than the disease being treated with the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

In certain embodiments, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be used in combination with DMF.

In certain embodiments, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be used in combination with MMF.

In certain embodiments, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be used in combination with N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.

In certain embodiments, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be used in combination with at least one other therapeutic agent. In certain embodiments, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be administered to a patient together with another compound for treating diseases and conditions including: adrenal leukodystrophy, Alexander Disease, Alper's Disease, balo concentric sclerosis, Canavan disease, central nervous system vasculitis, Charcott-Marie-Tooth Disease, childhood ataxia with central nervous system hypomyelination, diabetic retinopathy, graft versus host disease, hepatitis C viral infection, herpes simplex viral infection, human immunodeficiency viral infection, Krabbe Disease, lichen planus, macular degeneration, monomelic amyotrophy, neurodegeneration with brain iron accumulation, neuromyelitis optica, neurosarcoidosis, optic neuritis, paraneoplastic syndromes, Pelizaeus-Merzbacher disease, primary lateral sclerosis, progressive supranuclear palsy, Schilder's Disease, subacute necrotizing myelopathy, Susac's syndrome, transverse myelitis, a tumor, and Zellweger's syndrome.

Methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and the at least one other therapeutic agent may act additively or, and in certain embodiments, synergistically. The at least one additional therapeutic agent may be included in the same dosage form as methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate or may be provided in a separate dosage form. Methods provided by the present disclosure can further include, in addition to administering methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate, administering one or more therapeutic agents effective for treating the same or different disease than the disease being treated by methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. Methods provided by the present disclosure include administration of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and one or more other therapeutic agents provided that the combined administration does not inhibit the therapeutic efficacy of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and/or does not typically produce significant and/or substantial adverse combination effects.

In certain embodiments, dosage forms comprising methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be administered concurrently with the administration of another therapeutic agent, which may be part of the same dosage form as, or in a different dosage form than that comprising methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. Methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be administered prior or subsequent to administration of another therapeutic agent. In certain embodiments, the combination therapy may comprise alternating between administering methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and a composition comprising another therapeutic agent, e.g., to minimize adverse drug effects associated with a particular drug. When methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate is administered concurrently with another therapeutic agent that potentially may produce an adverse drug effect including, but not limited to, toxicity, the other therapeutic agent may advantageously be administered at a dose that falls below the threshold at which the adverse drug reaction is elicited.

In certain embodiments, dosage forms comprising methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be administered with one or more substances to enhance, modulate and/or control release, bioavailability, therapeutic efficacy, therapeutic potency, stability, and the like of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate. For example, to enhance the therapeutic efficacy of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate, the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be co-administered with or a dosage form comprising methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate and one or more active agents to increase the absorption or diffusion of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate from the gastrointestinal tract to the systemic circulation, or to inhibit degradation of the methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate in the blood of a patient. In certain embodiments, methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate may be co-administered with an active agent having pharmacological effects that enhance the therapeutic efficacy of methyl 4-morpholin-4-ylbutyl (2E)but-2-ene-1,4-dioate.

EXAMPLES

The following examples illustrate various aspects of the disclosure. It will be apparent to those skilled in the art that many modifications, both to materials and methods, may be practiced without departing from the scope of the disclosure.

Example 1: Photodegradation of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate under cool white fluorescent Light

Approximately 50 mg (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate powder was spread into a thin layer (˜1 mm) in open quartz containers. The sample was then placed in an ICH2 Photoreactor (Luzchem Research Inc.) with 16 cool white fluorescent lamps (F8T5/CW-8 Watt) installed. The light power was 22.8×10³ lux with low level of near UV light (320-400 nm) at 2.2 watt/m². The sample was taken out after 53 hours to achieve a light exposure of 1.2 million lux hours. The sample solution was prepared at 0.2 mg/mL in diluent (water/acetonitrile/H₃PO₄ (80/20/0.05 by volume)).

To quantify the photodegratation of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate powder, the presence of (N,N-diethylcarbamoyl)methyl (1S,3S,2R,4R)-2-{[(N,N-diethylcarbamoyl)methyl]oxycarbonyl}-3,4-bis(methoxycarbonyl)cyclobutanecarboxylate (“compound (1)”) was quantified. The structure of compound (1) is shown below:

The amount (weight percent) of compound (1) in the sample was determined by reverse phase HPLC using a C₁₈ column and a 30-minute gradient method according to Table 1 where Mobile Phase A is water/0.05% H₃PO₄ and Mobile Phase B is water/acetonitrile/H₃PO₄ (10/90/0.05 by volume) with UV detection at 210 nm. The amount of compound (1) found was 29.0 wt %.

TABLE 1 Gradient for HPLC Method Time % Mobile % Mobile (minutes) Phase A Phase B 0 98 2 6 65 35 15 55 45 25 10 90 25.1 98 2 30 98 2

Example 2: Photodegradation of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate under near-UV Light

Approximately 50 mg (N,N-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate powder was spread into a thin layer in open quartz containers. The sample was then placed in an ICH2 Photoreactor (Luzchem Research Inc.) with 16 near-UV fluorescent lamps (Hitachi FL8BL-B) installed. The near-UV light (320-400 nm) power was 94.2 watt/m². The sample was taken out after 2.1 hours to achieve a light exposure of 200 watt hour/m². The sample was prepared and analyzed the same way as described in Example 1. The amount of compound (1) found was 10.3 wt %.

Example 3: Photodegradation of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate in aqueous solution under cool white fluorescent Light

A quartz flask containing approximately 20 mL of 0.1 mg/mL (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate in 50 mM pH 4.0 citrate buffer was placed in an ICH2 Photoreactor (Luzchem Research Inc.) with 16 cool white fluorescent lamps (F8T5/CW-8 Watt) installed. The light power was 22.8×10³ lux with low level of near UV light (320-400 nm) at 2.2 watt/m². The sample was taken out after 53 hours to achieve a light exposure of 1.2 million lux hours.

To quantify the photodegratation of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate powder, the presence of (N,N-diethylcarbamoyl)methyl methyl (2Z)but-2-ene-1,4-dioate (“compound (2)”) was quantified. The structure for compound (2) is shown below:

The sample was analyzed using the same HPLC method as described in Example 1. The amount of compound (2) found was 22.3 wt %.

Example 4: Photodegradation of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate in aqueous solution under near-UV Light

A quartz flask containing approximately 20 mL of 0.1 mg/mL (NA-Diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate in 50 mM pH 4.0 citrate buffer was placed in an ICH2 Photoreactor (Luzchem Research Inc.) with 16 near-UV fluorescent lamps (Hitachi FL8BL-B) installed. The near-UV light (320-400 nm) power was 94.2 watt/m². The sample was taken out after 2.1 hours to achieve a light exposure of 200 watt hour/m². The sample was analyzed using the same HPLC method as described in Example 1. The amount of compound (2) found was 3.6 wt %.

Having described several embodiments, it will be recognized by those skilled in the art that various modifications, alternative constructions, and equivalents may be used without departing from the spirit of the disclosure. Additionally, a number of well-known processes and elements have not been described in order to avoid unnecessarily obscuring the embodiments disclosed herein. Accordingly, the above description should not be taken as limiting the scope of the document.

Those skilled in the art will appreciate that the presently disclosed embodiments teach by way of example and not by limitation. Therefore, the matter contained in the above description or shown in the accompanying drawings should be interpreted as illustrative and not in a limiting sense. The following claims are intended to cover all generic and specific features described herein, as well as all statements of the scope of the present method and system, which, as a matter of language, might be said to fall there between. 

We claim:
 1. A pharmaceutical dosage form for treating a disease in a patient, comprising: (a) a therapeutically effective amount of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate, wherein the therapeutically effective amount is from 1 mg to 600 mg; and (b) one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), or (XV):

N,N-diethyl-2-hydroxyacetamide, and salts of any of the foregoing, wherein: each of R¹ through R⁴ is independently chosen from hydrogen, methyl and (N,N-diethyl carbamoyl)methyl; each R⁵ and R⁷ is independently chosen from hydrogen, methyl, and (N,N-diethyl carbamoyl)methyl; Y is chosen from O, S, NH and NR⁸; R⁶ is chosen from hydrogen, lower alkyl, substituted lower alkyl, aryl, and substituted aryl; R⁸ is chosen from lower alkyl; each of R⁹ and R¹⁰ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl; each of R¹¹ and R¹² is independently chosen from hydrogen, methyl, and (N,N-diethyl carbamoyl)methyl; each of R¹³ and R¹⁴ is independently chosen from hydrogen, methyl, and (N,N-diethyl carbamoyl)methyl; Q is O—, —S—, —NH—, N(R′⁷)— or —C(R¹⁸)₂—; each of R¹⁵ and R¹⁶ is independently chosen from hydrogen, methyl, and (N,N-diethyl carbamoyl)methyl; R¹⁷ is (N,N-diethylcarbamoyl)methyl or alkyl; each R¹⁸ is independently hydrogen or alkyl; each of R³⁷ and R³⁸ is independently chosen from hydrogen, methyl, and (N,N-diethylcarbamoyl)methyl; R⁴¹ is (N,N-diethylcarbamoyl)methyl; R⁴² is chosen from hydrogen, ethyl, and (N,N-diethylcarbamoyl)methyl; and each of the one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), and (XV), and N,N-diethyl-2-hydroxyacetamide is present in the dosage form in an amount of about 0.001% to about 0.2% by weight based on total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.
 2. The dosage form of claim 1, wherein any one of the one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), and (XV), and N,N-diethyl-2-hydroxyacetamide is present in the dosage form in an amount of about 0.001% to about 0.1% by weight based on total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.
 3. The dosage form of claim 1, wherein the one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), and (XV), and N,N-diethyl-2-hydroxyacetamide is present in a combined total amount of about 0.001% to about 3% by weight based on total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.
 4. The dosage form of claim 1, wherein the one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), and (XV), and N,N-diethyl-2-hydroxy acetamide is present in a combined total amount of about 0.001% to about 2% by weight based on total weight of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.
 5. The dosage form of claim 1, wherein the one or more compounds of Formulae (I), (II), (III), (IV), (V), (VI), (XIII), and (XV) is selected from: Formula (I) compounds 1,2-bis((N,N-diethylcarbamoyl)methoxycarbonyl)-3,4-bis(methoxycarbonyl)cyclobutane; 1,3-((N,N-diethylcarbamoyl)methoxycarbonyl)-2,4-bis(methoxycarbonyl)cyclobutane; 1-(N,N-diethylcarbamoyl)methoxycarbonyl-2-methoxycarbonylcyclobutane-3,4-dicarboxylic acid; 1,2-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-2,3-dicarboxylic acid; 1,3-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-2,4-dicarboxylic acid; 1,2-bis(methoxycarbonyl)cyclobutane-3,4-dicarboxylic acid; 1,3-bis(methoxycarbonyl)cyclobutane-2,4-dicarboylic acid; cyclobutane-1,2,3,4-tetracarboxylic acid; 1,2-((N,N-diethylcarbamoyl)methoxycarbonyl)-3-methoxycarbonylcyclobutane-4-carboxylic acid; 1,2-bis(methoxycarbonyl)cyclobutane-3,4-dicarboxylic acid; 1,2-bis(methoxycarbonyl)-3-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-4-carboxylic acid; 1,2-((N,N-diethylcarbamoyl)methoxycarbonyl)-3-(methoxycarbonyl)cyclobutane-4-carboxylic acid; 1-((N,N-diethylcarbamoyl)methoxycarbonyl)-2,3-bis(methoxycarbonyl)cyclobutane-4-carboxylic acid; 1-((N,N-diethylcarbamoyl)methoxycarbonyl)cyclobutane-2,3,4-tricarboxylic acid; and 1-(methoxycarbonyl)cyclobutane-2,3,4-tricarboxylic acid; Formula (II) compounds (N,N-diethylcarbamoyl)methyl-methyl-hydroxysuccinate; methyl-hydroxysuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-hydroxysuccinic mono-acid; hydroxysuccinic acid; (N,N-diethylcarbamoyl)methyl-methyl-mercaptosuccinate; methylmercaptosuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-mercaptosuccinic mono-acid; mercaptosuccinic acid; (N,N-diethylcarbamoyl)methyl-methyl-aminosuccinate; methylaminosuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-aminosuccinic mono-acid; and aminosuccinic acid; Formula (III) compounds cis-(N,N-diethylcarbamoyl)methyl-methyl oxirane dicarboxylate; cis-(methoxycarbonyl)oxirane carboxylic mono-acid; cis-(N,N-diethylcarbamoyl)methoxycarbonyl oxirane carboxylic mono-acid; cis-oxirane 2,3-dicarboxylic acid; trans-(N,N-diethylcarbamoyl)methyl-methyl oxirane dicarboxylate; trans-(methoxycarbonyl)oxirane carboxylic mono-acid; trans-(N,N-diethylcarbamoyl)methoxycarbonyl oxirane carboxylic mono-acid; and trans-oxirane 2,3-dicarboxylic acid; Formula (IV) compounds (N,N-diethylcarbamoyl)methyl-methyl-succinate; methyl succinic mono-acid; ((N,N-diethylcarbamoyl)methyl)succinic mono-acid; and succinic acid; Formula (V) compounds (N,N-diethylcarbamoyl)methyl-methyl-2,3-dihydroxysuccinate; methyl-2,3-dihydroxysuccinic mono-acid; (N,N-diethylcarbamoyl)methyl-2,3-dihydroxysuccinic mono-acid; and 2,3-dihydroxysuccinic acid (tartaric acid); Formula (VI) compounds wherein: Q is —O—, and each IC and R¹⁶ is methyl; Q is —O—, and each R¹⁵ and R¹⁶ is H; Q is —O—, and each R¹⁵ and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —O—, R¹⁵ is H, and R¹⁶ is methyl; Q is —O—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —O—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —S—, and each of e and R¹⁶ is methyl; Q is —S—, and each of e and R¹⁶ is H; Q is —S—, and each of e and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —S—, R¹⁵ is H, and R¹⁶ is methyl; Q is —S—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —S—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —NH—, and each of e and R¹⁶ is methyl; Q is —NH—, and each of e and R¹⁶ is H; Q is —NH—, and each of e and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —NH—, R¹⁵ is H, and R¹⁶ is methyl; Q is —NH—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —NH—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —NMe-, and each of e and R¹⁶ is methyl; Q is —NMe-, and each of e and R¹⁶ is H; Q is —NMe-, and each of e and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —NMe-, R¹⁵ is H, and R¹⁶ is methyl; Q is —NMe-, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —NMe-, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —CH₂—, and each e and R¹⁶ is methyl; Q is —CH₂—, and each e and R¹⁶ is H; Q is —CH₂—, and each e and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Q is —CH₂—, R¹⁵ is H, and R¹⁶ is methyl; Q is —CH₂—, R¹⁵ is H, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; and Q is —CH₂—, R¹⁵ is methyl, and R¹⁶ is (N,N-diethylcarbamoyl)methyl; Formula (XIII) compounds (N,N-diethylcarbamoyl)methyl methyl maleate, (N,N-diethylcarbamoyl)methyl maleic acid, bis((N,N-diethylcarbamoyl)methyl) maleate, dimethyl maleate, methyl maleate, and maleic acid; Formula (XV) compounds (2E)-3-(((N,N-diethylcarbamoyl)methyl)oxycarbonyl)prop-2-enoic acid; (N,N-diethylcarbamoyl)methyl ethyl (2E)but-2-ene-1,4-dioate; and bis(N,N-diethylcarbamoyl)methyl(2E)but-2-ene-1,4-dioate; isomers of any of the foregoing compounds and salts of any of the foregoing compounds.
 6. The dosage form of claim 1 containing one or more compounds of Formula (I), wherein the one or more compounds of Formula (I) are 1R,2R,3S,4S-isomers.
 7. The dosage form of claim 1, including a pharmaceutically acceptable vehicle.
 8. The dosage form of claim 7, wherein the pharmaceutically acceptable vehicle is selected from a carrier, a diluent, an excipient, a wetting agent, an emulsifier, a buffer, a stabilizer, a thickener, a lubricant, a coloring agent, and combinations thereof.
 9. The dosage form of claim 1, in the form of a tablet or capsule.
 10. The dosage form of claim 9 containing a compound of Formula (I), comprising an opaque layer that is free of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.
 11. The dosage form of claim 1 containing a compound of Formula (II), wherein the dosage form is substantially free of materials that promote addition reactions of the (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.
 12. The dosage form of claim 11, wherein the dosage form is substantially free of alcohols, mercaptans, alkylamines and dialkylamines.
 13. The dosage form of claim 11, wherein the dosage form is substantially free of R⁶OH, R⁶SH, R⁶NH₂, and R⁶N(H)R⁸; wherein each of R⁶ and R⁸ is alkyl.
 14. The dosage form of claim 1 containing a compound of Formula (IV), wherein the dosage form is substantially free of any compound capable of facilitating the reduction of the double bond of (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate.
 15. The dosage form of claim 14, wherein the dosage form is substantially free of any compounds containing a hydrazino group.
 16. The dosage form of claim 1 containing a compound of Formula (V), comprising an antioxidant, a free radical scavenger or a combination thereof.
 17. The dosage form of claim 1 containing a compound of Formula (VI), wherein the dosage form is substantially free of materials that are capable of reacting with (N,N-diethylcarbamoyl)methyl methyl (2E)but-2-ene-1,4-dioate to form Diels-Alder products.
 18. The dosage form of claim 17, wherein the dosage form is substantially free of compounds containing cyclopentadiene, furan, thiophene, and pyrrole moieties.
 19. The dosage form of claim 1 containing a compound of Formula (III), wherein the dosage form is substantially free of PVP, PEG, and polysorbate surfactant.
 20. The dosage form of claim 1 containing a compound of Formula (III), comprising an antioxidant, a free radical scavenger or a combination thereof.
 21. The dosage form of claim 1, wherein the one or more compounds of Formula (III) comprises (N,N-diethylcarbamoyl)methyl methyl oxirane-2,3-dicarboxylate.
 22. A method of treating a disease in a patient, comprising administering to the patient a dosage form of claim
 1. 23. The method of claim 22, wherein the disease is selected from multiple sclerosis and psoriasis.
 24. The dosage form of claim 1, wherein the therapeutically effective amount is 300 mg to 600 mg.
 25. The dosage form of claim 1, wherein the therapeutically effective amount is 400 mg to 500 mg. 